This document discusses the fundamentals of photonic crystals and metamaterials. It defines photonic crystals as periodic optical nanostructures that affect photon motion similarly to how semiconductors affect electrons. Photonic crystals exhibit photonic band gaps where certain wavelengths of light are forbidden to propagate. Metamaterials are designed to interact with optical frequencies and contain nano-resonators that can produce negative permeability at optical frequencies. Challenges in constructing photonic materials at near-infrared and visible wavelengths involve nanoscale fabrication and resonance saturation.
Characterization of Photonic Crystal FiberSurbhi Verma
Photonic-crystal fiber (PCF) is a new class of optical fiber based on the properties of photonic crystals. Because of its ability to confine light in hollow cores or with confinement characteristics not possible in conventional optical fiber, PCF is now finding applications in fiber-optic communications, fiber lasers, nonlinear devices, high-power transmission, highly sensitive gas sensors, and other areas.
In this project, photonic crystal fibers and far field measurement technique was described. The project also focused on the development of analytical formulae and a method to characterize PCF from its far field radiation pattern using effective index approach considering PCF to be similar to single mode step index fiber. This project was an explanation of an already published research paper
Characterization of Photonic Crystal FiberSurbhi Verma
Photonic-crystal fiber (PCF) is a new class of optical fiber based on the properties of photonic crystals. Because of its ability to confine light in hollow cores or with confinement characteristics not possible in conventional optical fiber, PCF is now finding applications in fiber-optic communications, fiber lasers, nonlinear devices, high-power transmission, highly sensitive gas sensors, and other areas.
In this project, photonic crystal fibers and far field measurement technique was described. The project also focused on the development of analytical formulae and a method to characterize PCF from its far field radiation pattern using effective index approach considering PCF to be similar to single mode step index fiber. This project was an explanation of an already published research paper
Photonic crystals are periodic dielectric structures that have a band gap that forbids propagation of a certain frequency range of light. This property enables one to control light with amazing facility and produce effects that are impossible with conventional optics.Photonic crystals can be fabricated for one, two, or three dimensions. One-dimensional photonic crystals can be made of layers deposited or stuck together. Two-dimensional ones can be made by photolithography, or by drilling holes in a suitable substrate. Fabrication methods for three-dimensional ones include drilling under different angles, stacking multiple 2-D layers on top of each other, direct laser writing, or, for example, instigating self-assembly of spheres in a matrix and dissolving the spheres
This ppt give an idea about what metamaterial is? how are they formed? and introduces to the techniques to analyze them. A few applications of metamaterials are also mentioned.
Using Metamaterial as Optical Perfect AbsorberSepehr A. Benis
Article review and presentation on basics of using metamaterials as optical perfect absorbers
Metamaterial Course Final Project ( Optional Graduate Course )
Dr. Leyla Yousefi
This narrated power point presentation attempts to explain the fundamental principles of Photonic Crystal Fibers. The material will be useful for KTU final year students who prepare for the subject EC 405, Optical Communications.
DPS material
DNG material ( Do not depend on the chemical composition, Depend on the geometry of the structure units, Metamaterials are artificial engineered composite structures, Not commonly found in nature)
MNG material
ENG material
This presentation reviews the following paper.
Giannini, Vincenzo, Antonio I. Fernández-Domínguez, Susannah C. Heck, and Stefan A. Maier. "Plasmonic nanoantennas: fundamentals and their use in controlling the radiative properties of nanoemitters." Chemical reviews 111, no. 6 (2011): 3888-3912.
Metematterials are artificial structures designed to have unique properties not found in common materials such as negative refractive index, elasticity, can modify sound waves, enhance radiated power ect.
Photonic crystals are periodic dielectric structures that have a band gap that forbids propagation of a certain frequency range of light. This property enables one to control light with amazing facility and produce effects that are impossible with conventional optics.Photonic crystals can be fabricated for one, two, or three dimensions. One-dimensional photonic crystals can be made of layers deposited or stuck together. Two-dimensional ones can be made by photolithography, or by drilling holes in a suitable substrate. Fabrication methods for three-dimensional ones include drilling under different angles, stacking multiple 2-D layers on top of each other, direct laser writing, or, for example, instigating self-assembly of spheres in a matrix and dissolving the spheres
This ppt give an idea about what metamaterial is? how are they formed? and introduces to the techniques to analyze them. A few applications of metamaterials are also mentioned.
Using Metamaterial as Optical Perfect AbsorberSepehr A. Benis
Article review and presentation on basics of using metamaterials as optical perfect absorbers
Metamaterial Course Final Project ( Optional Graduate Course )
Dr. Leyla Yousefi
This narrated power point presentation attempts to explain the fundamental principles of Photonic Crystal Fibers. The material will be useful for KTU final year students who prepare for the subject EC 405, Optical Communications.
DPS material
DNG material ( Do not depend on the chemical composition, Depend on the geometry of the structure units, Metamaterials are artificial engineered composite structures, Not commonly found in nature)
MNG material
ENG material
This presentation reviews the following paper.
Giannini, Vincenzo, Antonio I. Fernández-Domínguez, Susannah C. Heck, and Stefan A. Maier. "Plasmonic nanoantennas: fundamentals and their use in controlling the radiative properties of nanoemitters." Chemical reviews 111, no. 6 (2011): 3888-3912.
Metematterials are artificial structures designed to have unique properties not found in common materials such as negative refractive index, elasticity, can modify sound waves, enhance radiated power ect.
Metamaterial is an arrangement of artificial structural elements, designed to achieve advantageous and unusual electromagnetic properties
meta = beyond (Greek)
Using Metamaterials as Optical Perfect AbsorberSepehr A. Benis
Article review and presentation on basics of using metamaterials as optical perfect absorbers
Metamaterial Course Final Project ( Optional Graduate Course )
Dr. Leyla Yousefi
A new design and a new application of a metamaterial that converts 36.8% of incident power from a 900 MHz signal into usable dc voltage.experimentally rectified by an array of metamaterial unit cells.
Study of highly broadening Photonic band gaps extension in one-dimensional Me...IOSR Journals
In this paper, we show theoretically that the reflectance spectra of one dimensional multilayer metal-organic periodic structure (1D MOPS) can be enhanced due to the addition of the organic constituents. We have used simple transfer matrix method to calculate the absorption, transmittance and reflectance of the 1D MOPS systems. The organic component like N,N’-bis-(1-naphthyl)-N,N’diphenyl-1; 1biphenyl-4; 4diamine (NPB) absorbs the light in ultra-violet, visible and infrared electromagnetic region and the structure with Ag-metal also having the tendency to absorb the light by the plasmaonic action and their refractive can be calculated from Drude equation. The reflectance spectra of multilayer 1D MOPS containing a variable number periodic of Ag/N,N’-bis-(1-naphthyl)-N,N’diphenyl-1; 1biphenyl-4; 4diamine (NPB) structure are calculated taking optical constant of NPB and Ag. The optical band gap and reflectance spectra of 1D MOPS of the considered structure is obtained in the visible and near infrared regions either with the variation of the metal layer thickness or thickness of the organic layer. From the results under investigation through TMM, tunability in the optical band gap was observed either change in thickness of the other layer 1/ or 2 or the angle of the incident. Due to optical absorption of the light in the different region of electromagnetic spectrum due to either N,N’-bis-(1-naphthyl)-N,N’diphenyl-1; 1biphenyl-4; 4diamine (NPB) or silver metal, the optical band gap of 1DMOPS shows the shift of band edges of λL and λR from ultra-violet to visible and the infrared with change the optical constant.
Calculation of Optical Properties of Nano ParticlePHYSICS 5535- .docxRAHUL126667
Calculation of Optical Properties of Nano Particle
PHYSICS 5535- Optical Properties Matter-Spring 2017
Raznah Yami
Outline
1. Introduction: this part gives a precise overview of the whole paper. It begins by illustrating a brief introduction and importance of Nano Particles and the theoretical approaches used for their calculation.
2. Main idea: this section provides a step-by-step in-depth analysis of recently developed theories the calculation of optical properties of nanoparticles. It also provides calculation and equations employed these approaches.
2.1 Optical Properties of Nanoparticles: this section talks about the basics principles and governing the optical behavior of Nano particles and provides in-depth knowledge of different phenomena observed while dealing with optical properties of Nano particles.
2.2 Mie-Theory: the research provides exhaustive information the study optical properties of nanoparticles using Mie theory. This research focuses on Mie theory for the calculation of optical properties of Nano particle according to which we can calculate the place of surface Plasmon resonance in optical spectra of metallic spherical nanoparticle.
2.3 Discrete Dipole Approximation method: this section enumerates sufficient information about the calculation of absorption and scattering efficiencies and optical resonance wavelengths for three commonly used classes of nanoparticles: gold Nano spheres, silica-gold Nano shells, and gold Nano rods and we examine the magneto-optical scattering from nanometer-scale structures using a discrete dipole approximation.
3. Conclusion: This section provides a summary of the most important points, which presents an overview of the practical application and calculation methods of optical properties of Nano particles talking about core principles, which therefore explain the behavior exhibited by nanoparticles.
List of figures:
Figure 1: Localized surface Plasmon resonance ,resulting from the collective oscillations of delocalized electrons in response to an external electric field
Figure 2: Absorption spectra of semiconductor nanoparticles of different diameter. Right-nanoparticles suspended in solution.
Figure 3: Comparison of absorbance along increasing wavelength between Nano GaAs (7-15 nm) and Bulk GaAs showing an apparent blue shift
Figure 4: Showing the effect of blue shift because of quantum confinement as the wavelength shifts from 1100 nm to 2000 nm when we move from particle size of 9nm to parcile size of 3 nm.
Figure 5: Emission spectra of several sizes of (Cdse) Zns core-shell quantum dots.
Figure 6: The optical spectra and transmission electron micrographs for the particles in vials 1–5 are also shown. Scale bars in micrographs are all 100 nm
Figure7: Shows the effect of varying relative core and shell thickness of gold Nano Shells, there is an apparent blue shift as the frequency increases
References:
1. . P. S. Per ...
Signal Degradation In Optical Fiber
Losses in an optical fibre:-
The types of losses in a optical fibre are
Attenuation loss
Absorption
Scattering
Bending loss
Dispersion loss
Coupling loss
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
2. Fundamentals of Crystals
Material properties are determined by the properties of their sub-units with
their spatial distribution.
Electromagnetic properties as a function of the ratio a the “lattice
constant” of the material/structure and λ the wavelength of the incoming
light (a/ ) can be organized in three large groups:
Natural crystals and metamaterials have lattice constants much smaller
than the light wavelengths: a << λ. These materials are treated as
homogeneous media with parameters ε and μ.
3. Fundamentals of Crystals
When a is in the same range of the wavelength of the incoming light one
defines a photonic crystal; a material with subunits bigger than atoms but
smaller than the EM wavelength.
In photonic crystals a is the distance between repeat units with a different
dielectric constant.
4. Photonics Crystals
Photonic crystals are periodic optical nanostructures that affect the
motion of photons in much the same way
that semiconductors affect electrons.
Photonic crystals have properties governed by the diffraction of the
periodic structures and may exhibit a band gap for photons.
Photons (behaving as waves) propagate through this structure – or not –
depending on their wavelength.
Wavelengths that are allowed to travel are known as modes; groups of
allowed modes form bands.
Disallowed bands of wavelengths are called photonic band gaps
5. Photonics Crystals
They typically are not described well using effective parameters ε and μ
and may be artificial or natural.
In 1987 Sajeev John and Eli Yablonovitch proposed of photonics crystals
with periodicity of n in 2D and 3D.
1D crystals (example Braggs Mirror or Distributed Bragg Reflector) were
known since 1887 .
6. Distributed Bragg Reflector
formed from multiple layers of alternating materials with varying refractive
index with each layer boundary causes a partial reflection of an optical
wave.
for waves whose wavelength is close to four times the optical thickness of
the layers, the many reflections combine with constructive interference,
and the layers act as a high-quality reflector.
The range of wavelengths that are reflected is called the photonic stop
band . Within this range of wavelengths, light is "forbidden" to propagate in
the structure.
12. Bragg’s Scattering
Regardless of how small the reflectivity r form an individual scatter, the
total reflectivity R for a semi-infinite structure is given by :
13. Photonic Band Gap
So light cannot propagate in a crystal when frequency of incident light
satisfies Bragg’s Condition :
Photonic Band Gap (PBG)
14. Photonic Band Gap
In a periodic system, when half the wavelength corresponds to the
periodicity i.e., λ/2 = a then Bragg’s Condition K= π/a prohibits photon
propagation
15. Band Structure of 1D Photonics Crystal
The dispersion curve of a 1D “photonic crystal” deviates from the straight-
line dispersion curve of a uniform bulk medium.
16. Band Structure of 1D Photonics Crystal
This is because at k=π/a formation of standing waves occur which have
zero group velocity discontinuity at that point
The energy of Standing waves being either in the high or the low index
regions therefore we have dielectric band & air band
21. Photonics in Nature
In Parides sesostris, the Emerald-patched Cattleheart butterfly, photonic
crystals are formed of arrays of Nano - sized holes in the chitin of the wing
scales.
The holes have a diameter of about 150 nanometers and are about the same
distance apart.
The holes are arranged regularly in small patches; neighboring patches
contain arrays with differing orientations.
The result is that these Emerald-patched Cattleheart scales reflect green light
evenly at different angles instead of being iridescent.
Iridescence is generally known as the property of certain surfaces that appear
to change color as the angle of view or the angle of illumination changes
23. Photonics Crystal Application
Most proposals for devices that make use of photonic crystals do not use
the properties of the crystal directly but make use of defect modes.
Such a defect is made when the lattice is changed locally. As a result, light
with a frequency inside the bandgap can now propagate locally in the
crystal, i.e. at the position of the defect.
24. Optical Fiber
An optical fiber is a cylindrical dielectric waveguide (non conducting
waveguide) that transmits light along its axis, by the process of total
internal reflection.
The fiber consists of a core surrounded by a cladding layer, both of which
are made of dielectric materials.
To confine the optical signal in the core, the refractive index of the core
must be greater than that of the cladding.
Light travels through the fiber core, bouncing back and forth off the
boundary between the core and cladding.
25. Photonic Crystal Fiber
Photonic crystal optic fibers are a special class of 2D photonic crystals
obtains its waveguide properties not from a spatially varying glass
composition but from an arrangement of very tiny and closely spaced air
holes which go through the whole length of fiber.
the simplest type of photonic crystal fiber has a triangular pattern of air
holes, with one hole missing i.e. with a solid core surrounded by an array of
air holes.
26. Photonic Crystal Fiber
The guiding properties of this type of PCF can be roughly understood with
an effective index model: the region with the missing hole has a higher
effective refractive index, similar to the core in a conventional fiber.
The gray area indicates glass, and the white circles air holes with typical
dimensions of a few micrometers.
27. Photonic Band Gap Fibers
based on a photonic bandgap of the cladding region
The refractive index of the core itself can be lower than that of the
cladding structure.
Essentially, a kind of two-dimensional Bragg mirror is employed.
28. Metamaterial Photonics
In photonic crystals, the size and periodicity of the scattering elements are
on the order of the wavelength rather than subwavelength.
subwavelength is used to describe an object having one or more
dimensions smaller than the length of the wave with which the object
interacts.
At optical frequencies(of GHz order) electromagnetic waves interact with
an ordinary optical material (e.g., glass) via the electronic polarizability of
the material.
This creates a state where the effective permeability of the material is
unity, μeff = 1
29. Metamaterial Photonics
Hence, the magnetic component of a radiated electromagnetic field has
virtually no effect on natural occurring materials at optical frequencies.
However, the proper design of the elementary building blocks of the
photonic metamaterial allows for a non-vanishing magnetic response and
even for μ<0 at optical frequencies.
Photonic metamaterials, are a type of electromagnetic
metamaterial, which are designed to interact with optical frequencies
which are terahertz (THz), infrared (IR), and eventually, visible wavelengths.
30. Structures Containing Nano-Resonators
Photonic metamaterials typically contain some kind of metallic
nanoscopic electromagnetic resonators.
An early approach, which has been taken over from previous work in the
microwave domain, is based on split-ring resonators.
The resonances of such a resonator can be in the mid-infrared domain
(with wavelengths of a few microns) when its width is reduced to the order
of a few hundred nanometers.
A magnetic field, oriented perpendicular to the plane of the rings, induces
an opposing magnetic field due to the Lenz’s law, which leads to a
diamagnetic response resulting in a negative permittivity in a certain
range of frequencies
32. Metamaterial Photonics
When light impinges such nano-resonators, it can excite electromagnetic
oscillations.
These are particularly strong for frequencies near the resonance
frequency.
As the period of the structure is well below half the optical wavelength,
there are no photonic bandgap effects, and the effect on light
propagation can be described with a (frequency-dependent) effective
relative permittivity ε and relative permeability μ of the metamaterial
33. Metamaterial Photonics
The electric resonances of individual nanorods originate from the
excitation of the surface waves on the metal air interface.
In a paired nanorod configuration two types of plasmon polariton waves
can be supported: symmetric and anti-symmetric.
34. Problems Encountered
Constructing Photonics Materials in near-infrared and visible frequencies
turned out not to be straightforward for at least two reasons:
1. technical challenges related to the fabrication of resonant structures on
the nanoscale .
2. resonance frequency saturates as the size of the SRR reduces, and the
amplitude of the resonant permeability decreases
Modern nanofabrication techniques such as Scanning Electron Beam
Lithography enable the fabrication of optical components on the scale of
the optical wavelength with a relative precision in the few nanometer
range
35. References
E. Yablonovitch, Phys. Rev. Lett. 58, 2059 (1987).
R. A. Depine and A. Lakhtakia (2004). "A new condition to identify isotropic
dielectric-magnetic materials displaying negative phase velocity".
Microwave and Optical Technology Letters 41.
Veselago, V. G. (1968). "The electrodynamics of substances with
simultaneously negative values of [permittivity] and [permeability]". Soviet
Physics Uspekhi 10 (4): 509–514.
36. References
S. John, Phys. Rev. Lett. 58, 2486 (1987).
Advances in Complex Artificial Electromagnetic Media by Nathan Kundtz
Department of Physics , Duke University.
K. Ohtaka, Phys. Rev. B 19, 5857 (1979)
Schurig,, D. et al. (2006). "Metamaterial Electromagnetic Cloak at
Microwave Frequencies".