Concept

Coefficient de Fresnel

Publications associées (211)

Distributed measurement of mode group effective refractive index difference in a few mode optical fibers

Luc Thévenaz, Zhisheng Yang, Alejandro Dominguez Lopez

The possibility to perform distributed measurements of the effective refractive index difference between distinct modes in few mode optical fibers is demonstrated using phase sensitive optical time domain reflectometry. Effective refractive index differenc ...

2022

General invariance and equilibrium conditions for lattice dynamics in 1D, 2D, and 3D materials

Nicola Marzari, Changpeng Lin, Samuel Poncé

The long-wavelength behavior of vibrational modes plays a central role in carrier transport, phonon-assisted optical properties, superconductivity, and thermomechanical and thermoelectric properties of materials. Here, we present general invariance and equ ...

NATURE PORTFOLIO2022

Lippmann Photography: A Signal Processing Perspective

Martin Vetterli, Arnaud Latty, Adam James Scholefield, Gilles Baechler, Michalina Wanda Pacholska

Lippmann (or interferential) photography is the first and only analog photography method that can capture the full color spectrum of a scene in a single take. This technique, invented more than a hundred years ago, records the colors by creating interferen ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Optical Diffraction Tomography Using Nearly In-Line Holography with a Broadband LED Source

Demetri Psaltis, Abhijit Roy, Ahmed Ayoub

We present optical tomography methods for a 3D refractive index reconstruction of weakly scattering objects using LED light sources. We are able to record holograms by minimizing the optical path difference between the signal and reference beams while sepa ...

MDPI2022

Three-dimensional ab initio description of vibration-assisted electron knock-on displacements in graphene

Mukesh Kumar Tripathi

Transmission electron microscopy characterization may damage materials, but an electron beam can also induce interesting dynamics. Elastic knock-on is the main electron irradiation damage mechanism in metals including graphene, and although atomic vibratio ...

AMER PHYSICAL SOC2022

Large Area Diamond Disk Growth Experiments and Thermomechanical Investigations for the Broadband Brewster Window in DEMO

Minh Quang Tran, Konstantinos Avramidis

An electron cyclotron system (ECS) is required in the European DEMO fusion reactor for plasma heating, magnetohydrodynamic control, especially the suppression of neoclassical tearing modes (NTMs), and thermal instability control. Microwave beams of 2 MW, g ...

2021

Sensing of Surface and Bulk Refractive Index Using Magnetophotonic Crystal with Hybrid Magneto-Optical Response

Serguei Sekatski

We propose an all-dielectric magneto-photonic crystal with a hybrid magneto-optical response that allows for the simultaneous measurements of the surface and bulk refractive index of the analyzed substance. The approach is based on two different spectral ...

2021

A phenomenological extended-reaction boundary model for time-domain wave-based acoustic simulations under sparse reflection conditions using a wave splitting method

Jan Sickmann Hesthaven

In environmental acoustics and in room acoustics, many surfaces exhibit extended-reaction (ER) behavior, i.e., their surface impedance varies with the angle of the incident sound wave. This paper presents a phenomenological method for modeling such angle d ...

ELSEVIER SCI LTD2021

Intraocular Lens Refractive Index and Its Impact on External Surface Reflections

Georges Wagnières

PURPOSE: To determine and compare the origin of the external surface reflections produced by commonly used intraocular lenses (IOLs). METHODS: The specular reflection taking place at the anterior surface of eight types of IOLs (IOL power = 22.00 diopters M ...

SLACK INC2021

Complementary Metasurfaces for Guiding Electromagnetic Wave

Mohammad Sajjad Mirmoosa

Metasurfaces can be employed for designing waveguides that confine the electromagnetic energy while they are open structures. In this communication, we introduce a new type of such waveguides, formed by two penetrable metasurfaces having complementary isot ...

2021

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