- If a slow mode in a photonic crystal corresponds to a regular band edge, incident light of that frequency will be totally reflected without producing the slow mode.
- Near a stationary inflection point (frozen mode regime), incident light can be linearly converted to the slow mode.
- At a degenerate band edge, incident light will be totally reflected but will create a diverging frozen mode inside a finite photonic crystal slab.
The experimental set up is enclosed in a highly evacuated glass vessel to avoid the deflection of silver atoms by gas. Each silver atom behaves like a magnet due to its magnetic moment resulting from spin angular momentum of its 5s1 electron. A beam of Silver atoms is passed in an inhomogeneous magnetic field. The silver atoms gets deflected in the inhomogeneous magnetic field due to the unequal forces experienced by poles of each 5s1 electron of an atom and is traced in a photographic plate. The presence of two curves on photographic film confirms that electron have spins either in clockwise or anticlockwise direction. The magnitude of the spacing between the curves on photographic film agrees well with experimental result. Thus, this experiment proves that space and spin of an electron is quantised and validates vector atom model.
We propose a possible experimental realization of a quantum analogue
of Newton's cradle using a configuration which starts from a
Bose-Einstein condensate. The system consists of atoms with two
internal states trapped in a one dimensional tube with a longitudinal
optical lattice and maintained in a strong Tonks-Girardeau regime at
maximal filling. In each site the wave function is a superposition of
the two atomic states and a disturbance of the wave function
propagates along the chain in analogy with the propagation of
momentum in the classical Newton's cradle. The quantum travelling
signal is generally deteriorated by dispersion, which is large for a
uniform chain and is known to be zero for a suitably engineered
chain, but the latter is hardly realizable in practice. Starting from
these opposite situations we show how the coherent behaviour can be
enhanced with minimal experimental effort.
The experimental set up is enclosed in a highly evacuated glass vessel to avoid the deflection of silver atoms by gas. Each silver atom behaves like a magnet due to its magnetic moment resulting from spin angular momentum of its 5s1 electron. A beam of Silver atoms is passed in an inhomogeneous magnetic field. The silver atoms gets deflected in the inhomogeneous magnetic field due to the unequal forces experienced by poles of each 5s1 electron of an atom and is traced in a photographic plate. The presence of two curves on photographic film confirms that electron have spins either in clockwise or anticlockwise direction. The magnitude of the spacing between the curves on photographic film agrees well with experimental result. Thus, this experiment proves that space and spin of an electron is quantised and validates vector atom model.
We propose a possible experimental realization of a quantum analogue
of Newton's cradle using a configuration which starts from a
Bose-Einstein condensate. The system consists of atoms with two
internal states trapped in a one dimensional tube with a longitudinal
optical lattice and maintained in a strong Tonks-Girardeau regime at
maximal filling. In each site the wave function is a superposition of
the two atomic states and a disturbance of the wave function
propagates along the chain in analogy with the propagation of
momentum in the classical Newton's cradle. The quantum travelling
signal is generally deteriorated by dispersion, which is large for a
uniform chain and is known to be zero for a suitably engineered
chain, but the latter is hardly realizable in practice. Starting from
these opposite situations we show how the coherent behaviour can be
enhanced with minimal experimental effort.
To detemine the wavelength of semiconductor laserPraveen Vaidya
The laser is part of almost all industrial sectors now. Laser is a coherent highly monochromatic concentrated beam of light.
Right from the computer data reading to metal welding the laser is used. The PowerPoint presentation here explains the laser experiment to determine the wavelength of a semiconductor laser, my the method of Grazing incidence (diffraction over the graduations of metal scale). The aim is to study the diffraction of patterns of laser scattered from the graduations of metal scale and hence determine the wavelength. The experiment is part of the physics curriculum in Technological universities and other science colleges.
To detemine the wavelength of semiconductor laserPraveen Vaidya
The laser is part of almost all industrial sectors now. Laser is a coherent highly monochromatic concentrated beam of light.
Right from the computer data reading to metal welding the laser is used. The PowerPoint presentation here explains the laser experiment to determine the wavelength of a semiconductor laser, my the method of Grazing incidence (diffraction over the graduations of metal scale). The aim is to study the diffraction of patterns of laser scattered from the graduations of metal scale and hence determine the wavelength. The experiment is part of the physics curriculum in Technological universities and other science colleges.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Dev Dives: Train smarter, not harder – active learning and UiPath LLMs for do...UiPathCommunity
💥 Speed, accuracy, and scaling – discover the superpowers of GenAI in action with UiPath Document Understanding and Communications Mining™:
See how to accelerate model training and optimize model performance with active learning
Learn about the latest enhancements to out-of-the-box document processing – with little to no training required
Get an exclusive demo of the new family of UiPath LLMs – GenAI models specialized for processing different types of documents and messages
This is a hands-on session specifically designed for automation developers and AI enthusiasts seeking to enhance their knowledge in leveraging the latest intelligent document processing capabilities offered by UiPath.
Speakers:
👨🏫 Andras Palfi, Senior Product Manager, UiPath
👩🏫 Lenka Dulovicova, Product Program Manager, UiPath
Builder.ai Founder Sachin Dev Duggal's Strategic Approach to Create an Innova...Ramesh Iyer
In today's fast-changing business world, Companies that adapt and embrace new ideas often need help to keep up with the competition. However, fostering a culture of innovation takes much work. It takes vision, leadership and willingness to take risks in the right proportion. Sachin Dev Duggal, co-founder of Builder.ai, has perfected the art of this balance, creating a company culture where creativity and growth are nurtured at each stage.
The Art of the Pitch: WordPress Relationships and SalesLaura Byrne
Clients don’t know what they don’t know. What web solutions are right for them? How does WordPress come into the picture? How do you make sure you understand scope and timeline? What do you do if sometime changes?
All these questions and more will be explored as we talk about matching clients’ needs with what your agency offers without pulling teeth or pulling your hair out. Practical tips, and strategies for successful relationship building that leads to closing the deal.
Accelerate your Kubernetes clusters with Varnish CachingThijs Feryn
A presentation about the usage and availability of Varnish on Kubernetes. This talk explores the capabilities of Varnish caching and shows how to use the Varnish Helm chart to deploy it to Kubernetes.
This presentation was delivered at K8SUG Singapore. See https://feryn.eu/presentations/accelerate-your-kubernetes-clusters-with-varnish-caching-k8sug-singapore-28-2024 for more details.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
"Impact of front-end architecture on development cost", Viktor TurskyiFwdays
I have heard many times that architecture is not important for the front-end. Also, many times I have seen how developers implement features on the front-end just following the standard rules for a framework and think that this is enough to successfully launch the project, and then the project fails. How to prevent this and what approach to choose? I have launched dozens of complex projects and during the talk we will analyze which approaches have worked for me and which have not.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
FIDO Alliance Osaka Seminar: Passkeys and the Road Ahead.pdf
Figotin Bath 2005
1. Alex Figotin & Ilya Vitebskiy University of California at Irvine Supported by AFOSR Slow light and resonance phenomena in photonic crystals September 2005
2. What are photonic crystals? Simplest examples of periodic dielectric structures Each constitutive component is perfectly transparent, while their periodic array may not transmit E.M. waves of certain frequencies (frequency gaps). 1D periodicity 2D periodicity n 1 n 2
3. Typical k diagram of a photonic crystal for a given direction of Bloch wave vector k Typical k diagram of a uniform anisotropic medium for a given direction of k . 1 and 2 denote two polarizations. ( k ) k ( k ) k 1 1 2 2
4. Slow light in photonic crystals: stationary points of dispersion relations Every stationary point of the dispersion relation ( k ) is associated with slow light. But there are some important differences between these cases. Fragment of dispersion relation with stationary points a , g and 0 . ω k g 0 a
5. What happens if the incident light frequency coincides with that of a slow mode? Will the incident light with the slow mode frequency s be converted into the slow mode inside the photonic crystal, or will it be reflected back to space? The answer depends on what kind of stationary point is associated with the slow mode. Reflected wave Incident wave of frequency s Passed slow mode Semi-infinite photonic crystal
6.
7. Slow mode amplitude at steady-state regime Incident wave S I Reflected wave S R Lossless semi-infinite photonic slab Transmitted slow mode S T ω k g 0
11. Space structure of the frozen mode Incident wave Ψ I Reflected wave Ψ R Lossless semi-infinite photonic slab Transmitted slow mode Ψ T
12. Distribution of EM field and its propagating and evanescent components inside semi-infinite slab at frequency close (but not equal) to 0 . The amplitude of the incident light is unity !!! a) resulting field | T ( z )| 2 = | pr ( z ) + ev ( z ) | 2 , b) extended Bloch component | pr ( z ) | 2 , c) evanescent Bloch component | ev ( z ) | 2 . As approaches 0 , | pr | 2 diverges as ( 0 ) 2/3 and the resulting field distribution | T ( z ) | 2 is described by quadratic parabola.
13. Summary of the case of a plane EM wave incident on semi-infinite photonic crystal : - If slow mode corresponds to a regular photonic band edge , the incident light of the respective frequency is totally reflected back to space without producing the slow mode in the periodic structure. - The incident light can be linearly converted into a slow mode only in the vicinity of stationary inflection point (the frozen mode regime). - If slow mode corresponds to degenerate photonic band edge , incident light of the respective frequency is totally reflected back to space. But in a steady-state regime it creates a diverging frozen mode inside the photonic crystal.
14. The question : Can the electromagnetic dispersion relation of a periodic layered structure (1D photonic crystal) display a stationary inflection point or a degenerate band edge? In other words, can a 1D photonic crystal display the frozen mode regime? The answer is : Stationary inflection point and degenerate band edge, along with associated with them the frozen mode regime can only occur in stacks incorporating anisotropic layers.
15. Simplest periodic layered arrays supporting stationary inflection point of the dispersion relation Non-magnetic periodic stack with oblique anisotropy in the A layers Magnetic periodic stack with misaligned in-plane anisotropy in the A layers z L A B A B A B A B A B A B z y x L A 1 A 2 F
16. Simplest periodic layered array capable of supporting degenerate photonic band edge There are three layers in a unite cell L . A pair of anisotropic layers A 1 and A 2 have misaligned in-plane anisotropy. The misalignment angle must be different from 0 and π /2 . B – layers can be made of isotropic material, for example, they can be empty gaps. The k diagram of the periodic stack is shown in the next slide. L z A 1 A 2 B A 1 A 2 B A 1 A 2 B A 1 A 2 B
17. The first band of the k diagram of the 3-layered periodic stack for four different values of the B - layer thickness. In the case (b) the upper dispersion curve develops degenerate band edge d . In the case (d) of B - layers absent, the two intersecting dispersion curves correspond to the Bloch waves with different symmetries; the respective eigenmodes are decoupled.
18. Up to this point we considered the frozen mode regime in semi-infinite photonic crystals. How important is the thickness of the photonic slab?
19. EM field distribution inside plane-parallel photonic crystal of thickness D at the frequency ω d of degenerate band edge. The incident wave amplitude is unity. The leftmost portion of the curves is independent of the thickness D . N = 256 N = 64 Frozen mode regime in finite periodic stacks
20. Transmission band edge resonance (Fabry-Perot cavity resonance in a finite periodic stack near the edge of a transmission band) k ω g D A B A B A B A B A B A B
22. Transmission band edge resonance: regular band edge Field intensity distribution at frequency of first transmission resonance Finite stack transmission vs. frequency
24. Finite stack transmission vs. frequency Field intensity distribution at frequency of first transmission resonance Transmission band edge resonance: degenerate band edge
25. Publications [1] A. Figotin and I. Vitebsky. Nonreciprocal magnetic photonic crystals. Phys. Rev. E 63, 066609, (2001) [2] A. Figotin and I. Vitebskiy. Electromagnetic unidirectionality in magnetic photonic crystals. Phys. Rev. B 67, 165210 (2003). [3] A. Figotin and I. Vitebskiy. Oblique frozen modes in layered media. Phys. Rev. E 68, 036609 (2003). [4] J. Ballato, A. Ballato, A. Figotin, and I. Vitebskiy. Frozen light in periodic stacks of anisotropic layers. Phys. Rev. E 71, 036612 (2005). [5] A. Figotin and I. Vitebskiy. Slow light in photonic crystals. Subm. to Waves in Random and Complex Media.(arXiv:physics/0504112 v2 19 Apr 2005). [6] A. Figotin and I. Vitebskiy. Gigantic transmission band edge resonance in periodic stacks of anisotropic layers. Phys. Rev. E 72 (2005).