Magnetic properties and superconductivity, meissner effect, superconductors, bcs theory, applications of superconductors, cooper pair, magnetic materials, hystersis, high temperature suerconductors, Types of suerconductors, high temperature superconductors, magnetism,right hand rule
Superconductivity is the ability of certain materials to conduct electric current with practically zero resistance. This capacity produces interesting and potentially useful effects. For a material to behave as a superconductor, low temperatures are required.
This document discusses various magnetic properties of materials. It defines magnetic induction, magnetic field intensity, and magnetic permeability. It describes diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, and ferrimagnetic materials. Diamagnetic materials have no unpaired electrons and are repelled by magnetic fields. Paramagnetic materials have some unpaired electrons and are weakly attracted to magnetic fields in a temperature-dependent manner. Ferromagnetic materials have strongly interacting unpaired electrons that align to produce spontaneous magnetization and strong attraction to magnetic fields.
This document discusses superconductors and their properties. It begins by defining superconductivity as the phenomenon where certain materials conduct electricity without resistance when cooled below a critical temperature. It then discusses key properties of superconductors including zero electrical resistance, the effects of impurities and pressure, isotope effects, magnetic field effects, critical current density, and the Meissner effect. It categorizes superconductors as either type 1 or type 2 and provides examples of each. Finally, it outlines several applications of superconductors such as magnetic levitation trains, SQUID devices, and RF/microwave filters.
This document provides information on various topics related to magnetism and magnetic materials:
1. It discusses different types of magnetic behavior such as diamagnetism, paramagnetism, and ferromagnetism. It also discusses the properties of hard and soft magnetic materials.
2. Key magnetic parameters are defined, including magnetic permeability, susceptibility, intensity of magnetization, Curie temperature, magnetic dipole moment, magnetic flux, and relative permeability.
3. The differences between diamagnetic, paramagnetic, and ferromagnetic materials are summarized in a table comparing their behaviors and properties.
4. The document also explains hysteresis loops, hard and soft magnets, and fer
This document discusses different types of magnetic materials:
- Diamagnetic materials do not have a permanent magnetic moment and are weakly repelled by magnetic fields. Paramagnetic materials have a permanent magnetic moment and are weakly attracted to magnetic fields. Ferromagnetic materials spontaneously magnetize in the absence of an external field due to the parallel alignment of atomic dipoles. Antiferromagnetic and ferrimagnetic materials also have permanent magnetic moments but their dipoles align antiparallel, resulting in weaker magnetization. Each category of material exhibits distinct magnetic behaviors that depend on temperature and applied magnetic fields.
This document provides an overview of superconductivity. It discusses key topics such as:
1. The discovery of superconductivity by Kamerlingh Onnes in 1911 and the properties of zero electrical resistance and the destruction of superconductivity by magnetic fields or currents.
2. The classification of Type I and Type II superconductors and their different responses to magnetic fields.
3. Theories that describe superconductivity such as the London equations, BCS theory, and Ginzburg-Landau theory.
4. Other properties like the Meissner effect, isotope effect, and persistent currents. Applications and the effect of variables like stress, frequency, and impurities are also covered
The liquid phase of matter has no definite shape but it has a definite volume. Liquids have no definite shape because the particles in a liquid are able to change position.
Superconductivity is the ability of certain materials to conduct electric current with practically zero resistance. This capacity produces interesting and potentially useful effects. For a material to behave as a superconductor, low temperatures are required.
This document discusses various magnetic properties of materials. It defines magnetic induction, magnetic field intensity, and magnetic permeability. It describes diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, and ferrimagnetic materials. Diamagnetic materials have no unpaired electrons and are repelled by magnetic fields. Paramagnetic materials have some unpaired electrons and are weakly attracted to magnetic fields in a temperature-dependent manner. Ferromagnetic materials have strongly interacting unpaired electrons that align to produce spontaneous magnetization and strong attraction to magnetic fields.
This document discusses superconductors and their properties. It begins by defining superconductivity as the phenomenon where certain materials conduct electricity without resistance when cooled below a critical temperature. It then discusses key properties of superconductors including zero electrical resistance, the effects of impurities and pressure, isotope effects, magnetic field effects, critical current density, and the Meissner effect. It categorizes superconductors as either type 1 or type 2 and provides examples of each. Finally, it outlines several applications of superconductors such as magnetic levitation trains, SQUID devices, and RF/microwave filters.
This document provides information on various topics related to magnetism and magnetic materials:
1. It discusses different types of magnetic behavior such as diamagnetism, paramagnetism, and ferromagnetism. It also discusses the properties of hard and soft magnetic materials.
2. Key magnetic parameters are defined, including magnetic permeability, susceptibility, intensity of magnetization, Curie temperature, magnetic dipole moment, magnetic flux, and relative permeability.
3. The differences between diamagnetic, paramagnetic, and ferromagnetic materials are summarized in a table comparing their behaviors and properties.
4. The document also explains hysteresis loops, hard and soft magnets, and fer
This document discusses different types of magnetic materials:
- Diamagnetic materials do not have a permanent magnetic moment and are weakly repelled by magnetic fields. Paramagnetic materials have a permanent magnetic moment and are weakly attracted to magnetic fields. Ferromagnetic materials spontaneously magnetize in the absence of an external field due to the parallel alignment of atomic dipoles. Antiferromagnetic and ferrimagnetic materials also have permanent magnetic moments but their dipoles align antiparallel, resulting in weaker magnetization. Each category of material exhibits distinct magnetic behaviors that depend on temperature and applied magnetic fields.
This document provides an overview of superconductivity. It discusses key topics such as:
1. The discovery of superconductivity by Kamerlingh Onnes in 1911 and the properties of zero electrical resistance and the destruction of superconductivity by magnetic fields or currents.
2. The classification of Type I and Type II superconductors and their different responses to magnetic fields.
3. Theories that describe superconductivity such as the London equations, BCS theory, and Ginzburg-Landau theory.
4. Other properties like the Meissner effect, isotope effect, and persistent currents. Applications and the effect of variables like stress, frequency, and impurities are also covered
The liquid phase of matter has no definite shape but it has a definite volume. Liquids have no definite shape because the particles in a liquid are able to change position.
The document discusses magnetic properties and their temperature dependence. It describes how saturation magnetization decreases with increasing temperature and disappears at the Curie point, above which materials become paramagnetic. It also discusses magnetic domains and how they form to minimize demagnetization fields. Hysteresis loops are described for soft and hard magnets, and their different applications and optimization. Superconductivity is introduced, noting the Meissner effect and resistance dropping to zero below the critical temperature.
Superconductivity is characterized by zero electrical resistance and the Meissner effect, where magnetic fields are expelled. There are two types of superconductors - Type I, which have an abrupt transition to the normal state, and Type II, which have a more gradual transition. The BCS theory explains superconductivity as electrons pairing up into Cooper pairs at low temperatures, acting as bosons that condense into the same quantum state. Superconductors have applications in medical imaging, maglev trains, and power transmission due to their ability to carry high currents and create strong magnetic fields.
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Superconductivity is a phenomenon where certain materials exhibit zero electrical resistance and expel magnetic fields when cooled below a critical temperature. Some key points:
- Superconductivity was first observed in mercury in 1911 by Kamerlingh Onnes, with resistance dropping to zero below 4.2K.
- Later, superconductors were found with higher critical temperatures, such as ceramics with critical temperatures up to 138K.
- The BCS theory explained superconductivity as arising from electrons forming Cooper pairs mediated by phonons, allowing them to flow without resistance.
- Applications of superconductors include maglev trains, MRI machines, power transmission lines, and quantum computing.
Basic Information regarding superconductors.
Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature.
This power-point presentation include
1. Introduction to Superconductors
2. Discovery
3. Properties
4. Important factors
5. Types
6. High Tc Superconductors
7. Magnetic Levitation and its application
8. Josephson effect
9. Application of superconductors
#Tip- You can further add videos which are available in vast amount on YouTube regarding superconductivity(specially magnetic levitation)
P.S.Does not contain information about Cooper pairs and BCS theory
This document defines magnetic terms and properties, describes different types of magnets, and explains how artificial magnets are produced. It discusses the permeability of various materials, magnetic fields and flux, and uses of the left-hand rule. Induction is demonstrated by magnetizing an iron bar near a permanent magnet. Practical applications of induction in electronics are also outlined, including uses in transmission, transformers, motors, and memory.
Superconductivity was discovered in 1911 by Heike Kamerlingh Onnes, who observed the electrical resistance of mercury abruptly disappeared at 4.2 K. Superconductivity occurs in certain materials at very low temperatures and is characterized by zero electrical resistance and perfect diamagnetism. The BCS theory from 1957 explained superconductivity as a superfluid of electron pairs called Cooper pairs that interact through phonon exchange. Superconductors exhibit properties like the Meissner effect, Josephson effect, and isotope effect. They are classified by critical temperature, magnetic response, and materials. Superconductors find applications in areas like magnetically levitated transportation, MRI machines, and power grid technologies.
The present article gives the fundamental properties magnetism, different materials, properties of different magnetic materials like, dia,para and ferro magnetic materials. The notes also explain how magnetism appear in materials, type of magnets and brief applications of magnetic materials. The materials is best for undergraduate science and engineering students and any other people of interest in magnetism
Hello, I am Subhajit Pramanick. I and my classmate, Anannya Sahaw, both presented this ppt in seminar of our Institute, Indian Institute of Technology, Kharagpur. The topic of this presentation is on exchange interaction and their consequences. It includes the basic of exchange interaction, the origin of it, classification of it and their discussions etc. We hope you will all enjoy by reading this presentation. Thank you.
weiss molecular theory of ferromagnetismsantoshkhute
Weiss' Theory (Domain theory of ferromag : According to weiss, a feromagnetic substance. contains atoms with permanent magnetic. moments, as in a paramagnetic substance, but due to special form of interaction.
A vibrating sample magnetometer (VSM) measures the magnetic properties of materials by vibrating a sample in a uniform magnetic field and measuring the magnetic moment. It works by vibrating a sample in between sensor coils within an electromagnet, which produces a magnetic field. The sensor coils detect the sample's magnetization and transmit the data to an amplifier, lock-in amplifier, and computer interface. VSMs can characterize the magnetic properties of powders, bulk materials, crystals, and single crystals. They are used to measure magnetic fields and determine the magnetic properties of minerals and ores.
This document discusses different types of magnetic materials classified by their magnetic susceptibilities. It describes diamagnetic, paramagnetic, ferromagnetic, ferrimagnetic, and antiferromagnetic materials. It also discusses the magnetic properties of soft and hard magnetic materials, and their uses in different industries. Additionally, it covers magnetic hysteresis, domains, and the crystal structures of perovskite metal oxides which are important for their magnetic properties.
The document discusses colossal magnetoresistance (CMR), where the electrical resistance of certain materials changes dramatically with an applied magnetic field. CMR was first observed in mixed-valence manganite materials and is caused by interactions between the electron spin, orbit, and lattice structure. Potential applications include smaller, higher capacity data storage devices. CMR remains an active area of research in physics and materials science due to its fundamental complexity and technological promise.
This document summarizes different types of magnetism, including diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, and ferrimagnetic. It discusses Curie's law and the Curie-Weiss law, which describe how magnetic susceptibility varies with temperature. The document also covers how to measure magnetic susceptibility using a Faraday balance or torsion balance, and how the magnetic behavior of different materials can be distinguished based on their magnetic susceptibility values and temperature dependence.
1. Magnetism arises from the magnetic moments of electrons, both from their orbital motion and spin.
2. Magnetic materials can be classified as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, or ferrimagnetic based on their magnetic properties.
3. Ferromagnetic materials exhibit hysteresis, where magnetization lags behind an applied magnetic field, leading to a hysteresis loop. Hard magnetic materials have large hysteresis loops while soft magnetic materials have small loops.
Basically i have tried giving every details about the phenomenon Superconductivity in the simplest way. This is my first upload.I'll be very glad if u all give your valuable feedback. Thank u.
This document provides information on magnetic materials and concepts. It discusses [1] the key differences between diamagnetism, paramagnetism and ferromagnetism. It also covers [2] the differences between hard and soft magnets, including their typical applications. Finally, it explains [3] several important magnetic parameters such as permeability, susceptibility, intensity of magnetization and hysteresis loops.
Order disorder transformation( the kinetics behind)Zaahir Salam
The document discusses order and disorder in physics systems. [1] Order refers to symmetry or correlation in particle systems, while disorder is the absence of order. [2] Systems typically change from ordered at low temperatures to less ordered states as they are heated through phase transitions. [3] Examples of order-disorder transitions include the melting of ice and the demagnetization of iron by heating.
- The Josephson effect describes the phenomenon of supercurrent flowing between two superconductors separated by a thin insulating barrier, known as a Josephson junction.
- The key equations governing the Josephson effect relate the supercurrent (I) flowing through the junction to the phase difference (φ) of the superconducting wave functions on either side of the barrier. A voltage (V) develops proportionally to the rate of change of the phase difference.
- Applications of the Josephson effect include SQUIDs for precision metrology, superconducting quantum computing using Josephson junctions as qubits, and superconducting tunnel junction detectors.
Ellipsometry- non destructive measuring methodViji Vijitha
Ellipsometry is a non-destructive optical technique that measures the change in polarization state of light upon reflection from or transmission through a sample. It can be used to characterize properties like thickness, composition, and crystallinity of thin films. The document discusses the history and principles of ellipsometry, experimental setups, data analysis techniques using modeling to extract sample properties, and applications in measuring films. Modeling involves using equations to describe light-material interactions and minimizing errors between calculated and measured polarization states.
This document discusses magnetic materials and their properties. It begins by explaining the origins of magnetism from electron orbits and spins. It then classifies magnetic materials as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, ferrimagnetic, and discusses their characteristics. The document also covers Weiss molecular field theory of ferromagnetism, hysteresis curves, hard and soft magnetic materials, ferrites and their applications. Finally, it discusses superconductivity including the BCS theory and applications of superconductors such as SQUIDs.
The document discusses magnetic properties and different types of magnetic materials. It defines key terms like magnetic field strength, induction, permeability, susceptibility, and saturation magnetization. It describes the origins of magnetic moments from orbital and spin motions. It classifies materials as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, or ferrimagnetic based on their relative magnetic permeabilities and behaviors in an external magnetic field. It explains the temperature dependence of magnetization and how thermal vibrations reduce the saturation magnetization above critical temperatures like the Curie or Neel points.
The document discusses magnetic properties and their temperature dependence. It describes how saturation magnetization decreases with increasing temperature and disappears at the Curie point, above which materials become paramagnetic. It also discusses magnetic domains and how they form to minimize demagnetization fields. Hysteresis loops are described for soft and hard magnets, and their different applications and optimization. Superconductivity is introduced, noting the Meissner effect and resistance dropping to zero below the critical temperature.
Superconductivity is characterized by zero electrical resistance and the Meissner effect, where magnetic fields are expelled. There are two types of superconductors - Type I, which have an abrupt transition to the normal state, and Type II, which have a more gradual transition. The BCS theory explains superconductivity as electrons pairing up into Cooper pairs at low temperatures, acting as bosons that condense into the same quantum state. Superconductors have applications in medical imaging, maglev trains, and power transmission due to their ability to carry high currents and create strong magnetic fields.
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Superconductivity is a phenomenon where certain materials exhibit zero electrical resistance and expel magnetic fields when cooled below a critical temperature. Some key points:
- Superconductivity was first observed in mercury in 1911 by Kamerlingh Onnes, with resistance dropping to zero below 4.2K.
- Later, superconductors were found with higher critical temperatures, such as ceramics with critical temperatures up to 138K.
- The BCS theory explained superconductivity as arising from electrons forming Cooper pairs mediated by phonons, allowing them to flow without resistance.
- Applications of superconductors include maglev trains, MRI machines, power transmission lines, and quantum computing.
Basic Information regarding superconductors.
Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in certain materials when cooled below a characteristic critical temperature.
This power-point presentation include
1. Introduction to Superconductors
2. Discovery
3. Properties
4. Important factors
5. Types
6. High Tc Superconductors
7. Magnetic Levitation and its application
8. Josephson effect
9. Application of superconductors
#Tip- You can further add videos which are available in vast amount on YouTube regarding superconductivity(specially magnetic levitation)
P.S.Does not contain information about Cooper pairs and BCS theory
This document defines magnetic terms and properties, describes different types of magnets, and explains how artificial magnets are produced. It discusses the permeability of various materials, magnetic fields and flux, and uses of the left-hand rule. Induction is demonstrated by magnetizing an iron bar near a permanent magnet. Practical applications of induction in electronics are also outlined, including uses in transmission, transformers, motors, and memory.
Superconductivity was discovered in 1911 by Heike Kamerlingh Onnes, who observed the electrical resistance of mercury abruptly disappeared at 4.2 K. Superconductivity occurs in certain materials at very low temperatures and is characterized by zero electrical resistance and perfect diamagnetism. The BCS theory from 1957 explained superconductivity as a superfluid of electron pairs called Cooper pairs that interact through phonon exchange. Superconductors exhibit properties like the Meissner effect, Josephson effect, and isotope effect. They are classified by critical temperature, magnetic response, and materials. Superconductors find applications in areas like magnetically levitated transportation, MRI machines, and power grid technologies.
The present article gives the fundamental properties magnetism, different materials, properties of different magnetic materials like, dia,para and ferro magnetic materials. The notes also explain how magnetism appear in materials, type of magnets and brief applications of magnetic materials. The materials is best for undergraduate science and engineering students and any other people of interest in magnetism
Hello, I am Subhajit Pramanick. I and my classmate, Anannya Sahaw, both presented this ppt in seminar of our Institute, Indian Institute of Technology, Kharagpur. The topic of this presentation is on exchange interaction and their consequences. It includes the basic of exchange interaction, the origin of it, classification of it and their discussions etc. We hope you will all enjoy by reading this presentation. Thank you.
weiss molecular theory of ferromagnetismsantoshkhute
Weiss' Theory (Domain theory of ferromag : According to weiss, a feromagnetic substance. contains atoms with permanent magnetic. moments, as in a paramagnetic substance, but due to special form of interaction.
A vibrating sample magnetometer (VSM) measures the magnetic properties of materials by vibrating a sample in a uniform magnetic field and measuring the magnetic moment. It works by vibrating a sample in between sensor coils within an electromagnet, which produces a magnetic field. The sensor coils detect the sample's magnetization and transmit the data to an amplifier, lock-in amplifier, and computer interface. VSMs can characterize the magnetic properties of powders, bulk materials, crystals, and single crystals. They are used to measure magnetic fields and determine the magnetic properties of minerals and ores.
This document discusses different types of magnetic materials classified by their magnetic susceptibilities. It describes diamagnetic, paramagnetic, ferromagnetic, ferrimagnetic, and antiferromagnetic materials. It also discusses the magnetic properties of soft and hard magnetic materials, and their uses in different industries. Additionally, it covers magnetic hysteresis, domains, and the crystal structures of perovskite metal oxides which are important for their magnetic properties.
The document discusses colossal magnetoresistance (CMR), where the electrical resistance of certain materials changes dramatically with an applied magnetic field. CMR was first observed in mixed-valence manganite materials and is caused by interactions between the electron spin, orbit, and lattice structure. Potential applications include smaller, higher capacity data storage devices. CMR remains an active area of research in physics and materials science due to its fundamental complexity and technological promise.
This document summarizes different types of magnetism, including diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, and ferrimagnetic. It discusses Curie's law and the Curie-Weiss law, which describe how magnetic susceptibility varies with temperature. The document also covers how to measure magnetic susceptibility using a Faraday balance or torsion balance, and how the magnetic behavior of different materials can be distinguished based on their magnetic susceptibility values and temperature dependence.
1. Magnetism arises from the magnetic moments of electrons, both from their orbital motion and spin.
2. Magnetic materials can be classified as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, or ferrimagnetic based on their magnetic properties.
3. Ferromagnetic materials exhibit hysteresis, where magnetization lags behind an applied magnetic field, leading to a hysteresis loop. Hard magnetic materials have large hysteresis loops while soft magnetic materials have small loops.
Basically i have tried giving every details about the phenomenon Superconductivity in the simplest way. This is my first upload.I'll be very glad if u all give your valuable feedback. Thank u.
This document provides information on magnetic materials and concepts. It discusses [1] the key differences between diamagnetism, paramagnetism and ferromagnetism. It also covers [2] the differences between hard and soft magnets, including their typical applications. Finally, it explains [3] several important magnetic parameters such as permeability, susceptibility, intensity of magnetization and hysteresis loops.
Order disorder transformation( the kinetics behind)Zaahir Salam
The document discusses order and disorder in physics systems. [1] Order refers to symmetry or correlation in particle systems, while disorder is the absence of order. [2] Systems typically change from ordered at low temperatures to less ordered states as they are heated through phase transitions. [3] Examples of order-disorder transitions include the melting of ice and the demagnetization of iron by heating.
- The Josephson effect describes the phenomenon of supercurrent flowing between two superconductors separated by a thin insulating barrier, known as a Josephson junction.
- The key equations governing the Josephson effect relate the supercurrent (I) flowing through the junction to the phase difference (φ) of the superconducting wave functions on either side of the barrier. A voltage (V) develops proportionally to the rate of change of the phase difference.
- Applications of the Josephson effect include SQUIDs for precision metrology, superconducting quantum computing using Josephson junctions as qubits, and superconducting tunnel junction detectors.
Ellipsometry- non destructive measuring methodViji Vijitha
Ellipsometry is a non-destructive optical technique that measures the change in polarization state of light upon reflection from or transmission through a sample. It can be used to characterize properties like thickness, composition, and crystallinity of thin films. The document discusses the history and principles of ellipsometry, experimental setups, data analysis techniques using modeling to extract sample properties, and applications in measuring films. Modeling involves using equations to describe light-material interactions and minimizing errors between calculated and measured polarization states.
This document discusses magnetic materials and their properties. It begins by explaining the origins of magnetism from electron orbits and spins. It then classifies magnetic materials as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, ferrimagnetic, and discusses their characteristics. The document also covers Weiss molecular field theory of ferromagnetism, hysteresis curves, hard and soft magnetic materials, ferrites and their applications. Finally, it discusses superconductivity including the BCS theory and applications of superconductors such as SQUIDs.
The document discusses magnetic properties and different types of magnetic materials. It defines key terms like magnetic field strength, induction, permeability, susceptibility, and saturation magnetization. It describes the origins of magnetic moments from orbital and spin motions. It classifies materials as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, or ferrimagnetic based on their relative magnetic permeabilities and behaviors in an external magnetic field. It explains the temperature dependence of magnetization and how thermal vibrations reduce the saturation magnetization above critical temperatures like the Curie or Neel points.
This document discusses the magnetic properties of materials. It begins by explaining that magnetism in solids originates from the orbital and spin motions of electrons and spins of nuclei. It then defines key terms like magnetization, magnetic moment, magnetic susceptibility, permeability, and Curie temperature. The document classifies magnetic materials into five types - diamagnetism, paramagnetism, ferromagnetism, antiferromagnetism, and ferrimagnetism - and provides examples of each. It concludes by explaining Langevin's classical theory of diamagnetism using an electron orbit model.
This document discusses various magnetic properties including magnetization, magnetic induction, magnetic field intensity, magnetic susceptibility, magnetic permeability, diamagnetism, paramagnetism, ferromagnetism, and superparamagnetism. It defines each property and provides examples. Diamagnetic materials are repelled by magnetic fields while paramagnetic and ferromagnetic materials are attracted. Ferromagnetic materials retain magnetization in the absence of an external field. Superparamagnetism occurs in nanoscale ferromagnetic particles that behave like paramagnets. Applications include MRI, cell separation, drug delivery, and sensors.
This document discusses various magnetic properties including magnetization, magnetic induction, magnetic field intensity, magnetic susceptibility, magnetic permeability, diamagnetism, paramagnetism, ferromagnetism, and superparamagnetism. Magnetization is defined as the magnetic dipole moment induced per unit volume. Magnetic induction is the process by which a substance becomes magnetized by an external magnetic field. Magnetic field intensity characterizes the external magnetic field excluding the material's internal field. Magnetic susceptibility is the ratio of magnetization to magnetic field intensity. Magnetic permeability is the ratio of magnetic induction to magnetic field intensity. Diamagnetism occurs in materials with paired electrons that produce an induced magnetic moment opposite to an external field. Paramagnet
1) Magnetism arises due to the orbital and spin motion of electrons in materials. The orbital motion of electrons gives rise to orbital magnetic moments, while the spin of electrons and nuclei gives rise to spin magnetic moments.
2) Magnetic materials can be classified as diamagnetic, paramagnetic, ferromagnetic, ferrimagnetic, or antiferromagnetic depending on their magnetic susceptibility and behavior in an applied magnetic field. Ferromagnetic materials like iron have the largest susceptibility.
3) The magnetic induction B in a material is proportional to the applied magnetic field strength H, with the constant of proportionality being the permeability μ of the material. The ratio of μ of a material to the permeability of free space is known as
This document provides an overview of magnetism and magnetic materials. It discusses magnetic field and flux density, Gauss's law for magnetism, Ampere's circuital law, Faraday's law of induction, magnetic permeability and susceptibility, and the classification of magnetic materials as diamagnetic, paramagnetic, or ferromagnetic. Key points include that magnetic field lines form closed loops, induced emf is proportional to the rate of change of magnetic flux, and ferromagnetic materials have large permeability and exhibit hysteresis.
Magnetism arises from the orbital and spin motions of electrons in atoms. There are several types of magnetism depending on how a material responds to an external magnetic field. Diamagnetism is a very weak form where the material opposes the external field. Paramagnetism is slightly stronger, where the material aligns with the field but does not retain magnetization when the field is removed. Ferromagnetism is the strongest form, where the material has permanent magnetic domains that strongly align with an external field and remain when it's removed. Ferromagnetism has subclasses of antiferromagnetism, where magnetic moments oppose each other resulting in no net magnetization, and ferrimagnetism where opposing moments do not
1. The document discusses magnetic methods for groundwater exploration. It covers topics such as the earth's magnetic field, magnetization of materials, magnetic anomalies over simple shapes, and magnetic surveying.
2. Key points include that magnetic surveying measures variations in the magnetic field to locate concentrations of magnetic materials. The magnetic susceptibility of rocks can vary significantly and influences the induced magnetization. Magnetic anomalies provide information on the location, size, and depth of magnetic sources like dykes.
3. Temporal variations in the earth's magnetic field like diurnal and secular changes need to be considered during data acquisition and processing to accurately interpret magnetic survey results.
1) Magnetism arises from the magnetic moments of electrons, which include orbital magnetic moments from electrons revolving around the nucleus and spin magnetic moments from electron spin.
2) Materials can be classified based on their magnetic properties as diamagnetic, paramagnetic, or ferromagnetic. Diamagnetic materials have no unpaired electrons and are weakly repelled by magnetic fields. Paramagnetic materials have some unpaired electrons and are weakly attracted to magnetic fields in their presence. Ferromagnetic materials have strongly interacting unpaired electrons that align to produce spontaneous magnetization even without an external field.
3) At the boundary between two magnetic materials, the tangential component of the magnetic field H is continuous, while the normal
A magnet produces a magnetic field that pulls on ferromagnetic materials like iron via attraction or repulsion. Magnetism originates from the orbital and spin motions of electrons, which produce magnetic moments. When a substance is placed in an external magnetic field, it exhibits different magnetic behaviors classified as diamagnetism, paramagnetism, ferromagnetism, or antiferromagnetism based on the sign and magnitude of susceptibility and dependence on field strength and temperature. Diamagnetic materials are repelled by a magnetic field while paramagnetic materials are attracted into a field. Ferromagnetism and antiferromagnetism arise from interactions between atomic spins in a crystal lattice.
1) The document discusses various magnetic properties including magnetic induction, magnetic field intensity, magnetic permeability, magnetization, and the origins of magnetism.
2) It describes different types of magnetic materials including diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, and ferrimagnetic materials.
3) The domain theory of ferromagnetism is explained, including the concepts of domains, domain walls, anisotropy energy, and hysteresis in ferromagnetic materials.
Magnetic Properties.pdf....................SONALIKABAL
Magnetism is the phenomenon by which materials exert attractive or repulsive forces on other materials. There are several types of magnetic behavior in materials. Diamagnetic materials are weakly repelled by magnetic fields and have a relative permeability slightly less than 1. Paramagnetic materials are weakly attracted to magnetic fields and have a relative permeability slightly greater than 1. Ferromagnetic materials strongly attract magnetic fields and can retain magnetization after an external magnetic field is removed. They have a very high relative permeability. Antiferromagnetic and ferrimagnetic materials also interact with magnetic fields but their magnetic moments partially or fully cancel each other out.
This document discusses the magnetic properties of materials. Some key points:
1. Magnetic properties are studied using parameters like magnetic dipoles, magnetization, magnetic susceptibility, and permeability. Materials respond differently to external magnetic fields based on these properties.
2. The magnetic moment of a material arises from the orbital and spin motions of electrons and the nuclear spin. Only partially filled electron shells contribute to the net magnetic moment.
3. Materials are classified as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, or ferrimagnetic based on their magnetic ordering and response to external fields. Ferromagnetic materials exhibit spontaneous magnetization from internal fields arising via exchange interactions between domains.
4. H
The document discusses dielectric materials and their polarization mechanisms when placed in an electric field. It explains that dielectrics do not allow electric charges to flow through but causes slight shifting of charges, creating an internal electric field. The main polarization mechanisms are electronic, ionic, dipolar, and space charge polarization.
It also discusses the origins of magnetic moments including electron spin and angular momentum. Ferromagnetic materials can be magnetized through domain growth/wall motion or rotation of domain magnetic moments in the direction of an applied magnetic field.
Hysteresis is defined as a lag between physical quantities when one is cyclically varied. The hysteresis loop illustrates how magnetic flux density B and field H vary during magnetization and dem
Fisika Zat Padat (12 - 14) b-diamagnetismjayamartha
The document discusses different types of magnetization in materials:
- Paramagnetic materials have atomic magnetic moments that align with an external magnetic field.
- Ferromagnetic materials also have atomic moments, and these moments strongly interact with neighboring moments, forming domains that retain magnetization.
- Diamagnetic materials do not have atomic moments but can develop induced moments that are repelled by an external magnetic field.
Magnetic materials can be classified as diamagnetic, paramagnetic, ferromagnetic, antiferromagnetic, or ferrimagnetic based on their response to an external magnetic field. Ferromagnetic materials like iron exhibit a strong attraction to magnetic fields and retain magnetization after the external field is removed due to the alignment of magnetic dipoles within domains. Ferrimagnetic materials like ferrites have anti-parallel dipoles of different magnitudes, producing a net magnetic moment. Magnetic semiconductors that exhibit both ferromagnetism and semiconductor properties have applications in spintronics and quantum computing.
This document discusses various topics related to magnetism:
1. Magnetism arises from atomic magnetic moments due to electron spin and orbital motion. Magnetic nanoparticles and magnetotactic bacteria use magnetism for navigation.
2. The magnetic moment of a current-carrying loop is given by m = IA. Key quantities in magnetism include magnetic moment, magnetic field strength, magnetization, magnetic induction, permeability, and magnetic susceptibility.
3. Different types of magnetism include diamagnetism, paramagnetism, ferromagnetism, antiferromagnetism, and ferrimagnetism. Diamagnetism is a weak, negative response to an applied magnetic field in all materials. Param
Magnetic materials are classified as those with and without permanent magnetic moments. Ferromagnetic materials have permanent magnetic moments below their Curie temperature due to spontaneous magnetization arising from spin exchange interaction between neighboring magnetic dipoles aligned in domains. When an external magnetic field is applied, the domains align by domain wall motion at weak fields and domain rotation at strong fields, producing hysteresis in the magnetization.
Similar to Magnetic properties and Superconductivity (20)
Current Ms word generated power point presentation covers major details about the micronuclei test. It's significance and assays to conduct it. It is used to detect the micronuclei formation inside the cells of nearly every multicellular organism. It's formation takes place during chromosomal sepration at metaphase.
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Abstract: Equivariant neural networks are neural networks that incorporate symmetries. The nonlinear activation functions in these networks result in interesting nonlinear equivariant maps between simple representations, and motivate the key player of this talk: piecewise linear representation theory.
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dtubbenhauer@gmail.com
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Context. With a mass exceeding several 104 M⊙ and a rich and dense population of massive stars, supermassive young star clusters
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2. Atoms are composed of protons, neutrons and electrons. Electrons carry a negative
electrical charge and produce a magnetic field as they move through space. A magnetic field is
produced whenever an electrical charge is in motion.
Magnetism is a phenomenon by which materials exert an attractive or repulsive force on
other materials. There are two types of magnetic poles, conventionally called north and
south.
Unlike electric charges, magnetic poles always occur in North-South pairs; there are no
magnetic monopoles.
MAGNETISM
In most atoms, electrons occur in pairs. Each electron in a pair spins in the opposite
direction. So when electrons are paired together, their opposite spins cause there magnetic
fields to cancel each other. Therefore, no net magnetic field exists. Alternately, materials with
some unpaired electrons will have a net magnetic field and will react more to an external field.
Most materials can be classified as diamagnetic, paramagnetic, or ferromagnetic.
3. DIRECTION OF MAGNETIC FIELD
When a current flows through a
conductor, a magnetic field surrounds
the conductor. As current flow
increases, so does the number of lines
of force in the magnetic field.
THE RIGHT HAND RULE
4. Permeability (μ)
This is the characteristic property of a medium.
It indicates the ease with which the material allows the
magnetic lines of force to pass through it.
OR
It is the measure of the ability of a material to support the
formation of a magnetic field within itself.
OR
In other words, it is the degree of magnetization that a material
obtains in response to an applied magnetic field.
0 r
μr- relative permeability of the medium
μ0 – permeability of free space or perme 4π×10−7 H.m-1
SI UNITS: Henry per meter(H.m-1), Newton per Ampere square (N.A-2)
5. Magnetic field intensity (H)
Magnetic field intensity at any point in the magnetic field is
the force experienced by an unit north pole placed at that point.
Magnetic susceptibility ( ):
Magnetic susceptibility is the degree of magnetization of a
material in response to an applied magnetic field.
HM
HM
The proportionality constant is called susceptibility. Its value may be
zero, positive or negative.
Where
M is magnetization,
H is magnetic field intensity
6. The magnetic induction and magnetic field intensity are related by
In vacuum HB 0
HB )1(0
HB
0 r
In a medium
)(0 MHB
, Since M=0
)1( r
Since,
HM )(0 MHB
where Relative permeability
7. Quantity Symbol
SI Units
(Sommerfeld)
SI Units
(Kennelly)
CGS Units
(Gaussian)
Field H A/m A/m Oersteds
Flux Density
(Magnetic
Induction)
B Tesla Tesla Gauss
Flux f Weber Weber Maxwell
Magnetization M A/m - erg/Oe-cm3
Conversion between CGS and SI magnetic units.
8. EFFECTS OF TEMPERATURE:CURIE AND CURIE-
WEISS LAWS
Curie’s law states that the magnetic susceptibility is inversely proportional
to temperature.
χ=C/T C-Curie constant
Many paramagnetic substances obey Curie law, especially at high
temperatures.
Curie-Weiss law better fit to the experimental data
χ=C/T+θ
Ferromagnetic materials show a very large susceptibility at low
temperature.
Above a certain temperature(ferromagnetic Curie temperature Tc),
ferromagnetic materials reverts to paramagnetic, where Curie-Weiss law is
usually observed.
9. CLASSIFICATION OF MAGNETIC MATERIALS
DIAMAGNETISM
PARAMAGNETISM
FERROMAGNETISM
FERRIMAGNETISM
ANTIFERROMAGNETISM
10. DIAMAGNETISM
Diamagnetism characterizes the substances that have only non-
magnetic atoms (lack of permanent diople moment).
Origin:
• An electron moving around the nucleus results in magnetic
moment.
• Due to different orientations of various orbits of an atom, the
net magnetic moment is zero in diamagnetic materials.
• When an external field is applied the motion of electrons in
their orbits changes resulting in induced magnetic moment in a
direction opposite to the direction of applied field.
11. The magnetization induced by the applied magnetic field is very weak
and the magnetic lines of force are repelled.
This magnetism is also exist in substances with magnetic atoms, but very
weak and completely masked by the contribution of magnetic atoms.
Relative permeability is slightly less than unity.
The magnetic susceptibility is independent of applied magnetic field
strength.
Magnitude of
susceptibility
Temperature dependence Examples
Small & negative Independent Organic materials,
light elements
Intermediate &
negative
Below 20K varies with field and
temperature
Alkali earths,
Bismuth
Large & Negative Exists only below critical
temperature (Meissner effect)
Superconducting
materials
12. PARAMAGNETISM
The paramagnetic substances consists of magnetic atom that
posses permanent dipole moment
Origin
Each electron in an orbit has an orbital magnetic moment and a
spin magnetic moment.
When the shells are unfilled there is net magnetic moment.
In the absence of the external field the net moments of the
atoms are arranged in random directions because of thermal
fluctuations. Hence there is no magnetization.
When external magnetic field is applied, there is tendency for the
dipoles to align with the field giving rise to an induced positive
dipole moment.
The induced magnetism is the source for paramagnetic behaviour.
13. Paramagnetic susceptibility is small and positive and is
independent of applied field strength.
Spin alignment is random.
Magnitude of
susceptibility
Temperature dependence Examples
Small & positive Independent Alkali metals,
transition
metals, rare
earths
Large & positive Curie law
Curie-Weiss law
T
C
T
C
14. FERROMAGNETISM
Even in the absence of external applied field, some substances
exhibits strong magnetization.
This is due to a special form of interaction called exchange coupling
between adjacent atoms that results in spontaneous magnetization
of the substance.
When placed inside a magnetic field, it attracts the magnetic lines
of force very strongly.
Each ferromagnetic material has a characteristic temperature
called the ferromagnetic Curie temperature θf. Below this
temperature the spontaneous magnetization exists.
15. Magnitude of
susceptibility
Temperature dependence Examples
Very large &
positive
For T>θf paramagnetic behavior
For T<θf ferromagnetic behavior
Fe, Co, Ni, Gd
T
C
Spin alignment is parallel.
Ferromagnetic materials exhibit Hysteresis.
They Consists of a number of small regions which are called domains.
16.
17. ANTI-FERROMAGNETISM
Antiferromagnetism macroscopically similar to paramagnetism, is a weak
form of magnetism.
In certain materials when the distance between the interacting atoms is
small the exchange forces produce a tendency for antiparallel alignment of
electron spins of neighboring atoms.
The magnetic susceptibility increase with the increase of temperature and
reaches maximum at a certain temperature. This temperature is known as
Neel temperature (TN). Above this temperature the susceptibility again
decreases.
18. Spins are aligned antiparallel
Magnitude of
susceptibility
Temperature dependence Examples
small & positive when T>TN
when T<TN
Salts of
transition
metals
T
C
T
19. FERRIMAGNETISM
This is a special case of antiferromagnetism.
The net magnetization of magnetic sublattices is not zero, since
antiparallel moments are of different magnitudes.
Hence ferrimagnetic materials possesses a net magnetic moment.
This moment disappears above a Curie temperature analogous to the
Neel temperature.
Above TC, thermal energy randomizes the individual magnetic
moments and the material becomes paramagnetic.
20. Ferrimagnetic domains become magnetic bubbles to act as memory
elements.
Spin alignment is antiparallel of different magnitudes.
Magnitude of
susceptibility
Temperature dependence Examples
Very large &
positive
when T>TN
when T<TN behaves as paramagnetic
material
Ferrites
T
C
21. HYSTERESIS
Hysteresis of ferromagnetic materials refers to the lag of magnetization
behind the magnetizing field.
A hysteresis loop is a curve showing the change in
magnetic induction of a ferromagnetic material
with an external field.
When the external magnetic field is increased the
magnetic induction increases.
22. Once magnetic saturation has been achieved, a decrease in the
applied field back to zero results in a macroscopically permanent
or residual magnetization, known as remanance, Mr. The
corresponding induction, Br, is called retentivity or remanent
induction of the magnetic material. This effect of retardation by
material is called hysteresis.
The magnetic field strength needed to bring the induced
magnetization to zero is termed as coercivity, Hc. This must be
applied anti-parallel to the original field.
A further increase in the field in the opposite direction results in
a maximum induction in the opposite direction. The field can once
again be reversed, and the field-magnetization loop can be closed,
this loop is known as hysteresis loop or B-H plot or M- H plot.
23.
24. DISCOVERY OF SUPERCONDUCTIVITY
Kamerlingh Onnes passed a current through a
very pure mercury wire and measured its
resistance as he steadily lowered the
temperature. Much to his surprise there was no
resistance at 4.2K.
1913
25. SUPERCONDUCTIVITY
Superconductivity is a quantum state of matter and it is the phenomenon of
exactly zero electrical resistance and expulsion of magnetic fields occurring in
certain materials when cooled below a characteristic critical temperature.
ZERO ELECTRICAL
RESISTANCE
EXPULSION OF
MAGNETIC FIELD
No collisions!!
No energy loss!!
IDEAL DIAMAGNETISM
26. The superconducting state is defined by three very important factors:
critical temperature (Tc), critical field (Hc), and critical current density
(Jc). Each of these parameters is very dependent on the other two
properties present
•Critical temperature (Tc) The highest temperature at which
superconductivity occurs in a material. Below this transition
temperature T the resistivity of the material is equal to zero.
•critical magnetic field (Hc ) Above this value of an externally applied
magnetic field a superconductor becomes nonsuperconducting.
•critical current density (Jc) The maximum value of electrical current
per unit of cross-sectional area that a superconductor can carry
without resistance.
27. CHARACTERISTICS PROPERTIES OF A SUPERCONDUCTOR :
FACTOR AFFECTING
Temperature : If a ring made of superconducting material is cooled in a magnetic field from ordinary
temperature to a value below its critical temperature and then the magnetic field is removed, an induced
current is set up in the ring. The resistance in the superconducting state being practically zero, the decay of
this induced current will take infinitely long time.
Magnetic field : Application of magnetic field to a superconducting specimen brings a stage when for
H=Hc, the critical field, the superconductor behaves like a normal material i.e., the superconductivity
disappears.
Current : If the magnetic field around the superconductor is increased beyond the critical field the
superconductivity is destroyed and the sample behaves as a normal material. Therefore the supercurrent will
flow only up to its critical value .Once the field exceeds Hc(T) the current becomes just the ordinary current.
28. Stress : Application of stress increases the transition temperature. As Hc(T) is temperature
dependent, increased stress is found to result in a slight change of Hc(T).
Size : Size of specimen exhibiting superconductivity is an important parameter for its behaviour.
Impurity : The presence of impurities changes almost all properties of a superconductor
especially its magnetic behaviour.
Isotopic Constitution of the Specimen : The critical temperature of a
specimen depends on the isotopic mass. The presence of various isotopes in a given specimen
decided what its average isotope mass will be. The dependence of Tc on such a mass is also called
Isotope Effect.
MaTc = constant or Tc M-1/2
30. BCS THEORY OF SUPERCONDUCTIVITY
John Bardeen Leon Cooper Bob Schrieffer
“ B. C. S.”
The BCS theory successfully shows that electrons can be attracted to
one another through interactions with the crystalline lattice. This
occurs despite the fact that electrons have the same charge.
When the atoms of the lattice oscillate as positive and negative
regions, the electron pair is alternatively pulled together and pushed
apart without a collision.
The electron pairing is favorable because it has the effect of putting
the material into a lower energy state.
When electrons are linked together in pairs, they move through the
superconductor in an orderly fashion.
1972
31. Cooper Pair:
• Two electrons that appear to "team up" in accordance with theory - BCS
or other - despite the fact that they both have a negative charge and
normally repel each other. Below the superconducting transition
temperature, paired electrons form a condensate - a macroscopically
occupied single quantum state - which flows without resistance
Leon Cooper
34. HIGH TEMPERATURE SUPERCONDUCTIVITY
High-temperature superconductors (abbreviated high-Tc or HTS) are materials that behave
as superconductors at unusually high temperatures..The first high-Tc superconductor was discovered in
1986 by IBM researchers Georg Bednorz and K. Alex Müller, who were awarded the 1987 Nobel Prize in
Physics "for their important break-through in the discovery of superconductivity in ceramic materials".
Type-II superconductors are usually made of metal alloys or complex oxide ceramics. All high
temperature superconductors are type-II superconductors. While most elemental superconductors are
type-I, niobium, vanadium and technetium are elemental type-II superconductors. Boron-
doped diamond and silicon are also type-II superconductors. Metal alloy superconductors also exhibit
type-II behavior (e.g.niobium-titanium and niobium-tin).
Other type-II examples are the cuprate-perovskite ceramic materials which have achieved the highest
superconducting critical temperatures. These include La1.85Ba0.15CuO4, BSCCO, and YBCO (Yttrium-
Barium-Copper-Oxide), which is famous as the first material to achieve superconductivity above the
boiling point of liquid nitrogen (77 K). Due to strong vortex pinning, the cuprates are close to ideally
hard superconductors.
35. DISCOVERY OF HIGH TEMPERATURE SUPERCONDUCTIVITY
In 1986, 75 years after the discovery of
superconductivity, George Bednorz and Karl Müller
at IBM, Zurich demonstrated superconductivity in a
perovskite structured lanthanum based cuprate
oxide which showed a Tc of 35 K for which the
inventors also won Physics Noble prize in 1987.
1987
PRESS RELEASE
38. High-transition-temperature (Tc) superconductivity in copper oxides (cuprates) is one of the most
intriguing emergent phenomena in strongly correlated electron systems.
It has attracted great attention since its discovery because Tc can exceed the boiling temperature of
liquid nitrogen, which is much higher than the putative limit of Tc ~ 40 K derived from the BCS theory for
conventional superconductivity.
The cuprate superconductors have a layered crystal structure consisting of CuO2 planes separated by
charge reservoir layers, which may dope electrons or holes into the CuO2 planes.
On doping holes, the antiferromagnetic Mott insulating phase of the parent compounds disappears and
superconductivity emerges. Tc follows a dome-like shape as a function of doping, with a
maximum Tc around 16% doped per CuO2 plaquette.
A similar phase diagram is seen on doping electrons, albeit with a more robust antiferromagnetic phase
and a lower Tc. On the hole-doped side, there exists an enigmatic state above Tc called the pseudogap,
where the electron density of states within certain momentum region is suppressed.
41. TELECOMMUNICATIONS
• Superconductors are used as efficient filters in
cellular telephone towers (now 700 worldwide)
• Separate signals of individual phone calls.
• Because of electrical resistance, conventional
interference filters eat away part of the signal.
TRANSMISSION LINES
• 15% of generated electricity is dissipated in transmission
lines
• Potential 100-fold increase in capacity
• BNL Prototype: 1000 MW transported in a diameter of
40 cm
TELECOMMUNICATIONS