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The concept of synthetic dimensions, which has enabled the study of higher-dimensional physics on lower-dimensional physical structures, has generated significant recent interest in many branches of science ranging from ultracold-atomic…

Optics · Physics 2020-01-07 Avik Dutt , Qian Lin , Luqi Yuan , Momchil Minkov , Meng Xiao , Shanhui Fan

In this paper, we investigate wave scattering by a pair of closely spaced inclusions embedded in a homogeneous medium, characterized by a high contrast physical parameters. The system is modeled by the two-dimensional Helmholtz equation. We…

Analysis of PDEs · Mathematics 2025-11-21 Hongjie Dong , Hongjie Li , Longjuan Xu

A wedge-shaped structure made of split-ring resonators (SRR) and wires is numerically simulated to evaluate its refraction behavior. Four frequency bands, namely, the stop band, left-handed band, ultralow-index band, and positive-index…

Optics · Physics 2007-05-23 Z. G. Dong , S. N. Zhu , H. Liu , J. Zhu , W. Cao

We study time-dependent acoustic and electromagnetic waves governed by the scalar wave equation or Maxwell's equations in a bounded three-dimensional domain. We establish the existence of time-dependent boundary excitations that can be…

Analysis of PDEs · Mathematics 2026-03-03 Roland Griesmaier , Soumen Senapati

When waves propagate through a complex medium like the turbulent atmosphere the wave field becomes incoherent and the wave intensity forms a complex speckle pattern. In this paper we study a speckle memory effect in the frequency domain and…

Analysis of PDEs · Mathematics 2022-01-17 Josselin Garnier , Knut Solna

The design of optical resonant systems for controlling light at the nanoscale is an exciting field of research in nanophotonics. While describing the dynamics of systems with few resonances is a relatively well understood problem,…

Optics · Physics 2020-02-20 M. Makarenko , A. Burguete-Lopez , F. Getman , A. Fratalocchi

We provide a theoretical description of light scattering by a spherical particle whose permittivity is modulated in time at twice the frequency of the incident light. Such a particle acts as a finite-sized photonic time crystal and, despite…

The scattering of quasiperiodic waves for a two-dimensional Helmholtz equation with a constant refractive index perturbed by a function which is periodic in one direction and of finite support in the other is considered. The scattering…

Mathematical Physics · Physics 2019-10-23 P. Zhevandrov , A. Merzon , M. I. Romero Rodríguez , J. E. de la Paz Méndez

We present an effective medium description of time-modulated dielectric media. By taking the averaged fields over one modulation period, the relationship between them is derived, defining therefore the different constitutive parameters. In…

Optics · Physics 2021-01-04 Dani Torrent

We report on the frequency conversions of terahertz (THz) waves at ultrafast time boundaries created via femtosecond laser-induced air-to-plasma phase transitions. Our combined experimental and theoretical approach reveals that the abrupt…

We prove the possibility of achieving exponentially growing wave propagation in space-time modulated media and give an asymptotic analysis of the quasifrequencies in terms of the amplitude of the time modulation at the degenerate points of…

Analysis of PDEs · Mathematics 2022-06-30 Habib Ammari , Jinghao Cao , Xinmeng Zeng

Physical systems with material properties modulated in time provide versatile routes for designing magnetless nonreciprocal devices. Traditionally, nonreciprocity in such systems is achieved exploiting both temporal and spatial modulations,…

A possibility to realize isotropic artificial backward-wave materials is theoretically analyzed. An improved mixing rule for the effective permittivity of a composite material consisting of two sets of resonant dielectric spheres in a…

Materials Science · Physics 2015-06-25 L. Jylha , I. Kolmakov , S. Maslovski , S. Tretyakov

This paper addresses the problem of efficiently jointly representing a non-stationary multicomponent signal in time and frequency. We introduce a novel enhancement of the time-reassigned synchrosqueezing method designed to compute sharpened…

Signal Processing · Electrical Eng. & Systems 2019-07-23 Dominique Fourer , François Auger

The ability to detect quantum superpositions lies at the heart of fundamental and applied aspects of quantum mechanics. The time-frequency degree of freedom of light enables encoding and transmitting quantum information in a…

Optics · Physics 2026-04-03 Adam Widomski , Maciej Ogrodnik , Michał Karpiński

Linear mechanical systems with time-modulated parameters can harbor oscillations with amplitudes that grow or decay exponentially with time due to the phenomenon of parametric resonance. While the resonance properties of individual…

Classical Physics · Physics 2024-08-06 Abhijeet Melkani , Jayson Paulose

Optical fibres constitute an exceptional sensing platform. However, standard fibres present an inherent sensing challenge: they confine light by design to an inner core. Consequently, nearly all distributed fibre sensors are restricted to…

Optics · Physics 2018-11-21 Gil Bashan , Hilel Hagai Diamandi , Yosef London , Eyal Preter , Avi Zadok

We demonstrate results of a simulation of nonlinear reflection of intensive terahertz radiation from a silicon-on-metal metasurface involving an excitation of a high-Q trapped mode resonance. Conditions are presented to observe effects of…

Applied Physics · Physics 2019-03-15 N V Sydorchuk , S L Prosvirnin , Y Fan , F Zhang

Modulation of metasurfaces in time gives rise to several exotic space-time scattering phenomena by violating the reciprocity and generation of higher-order frequency harmonics. We introduce a new design paradigm for time-modulated…

Applied Physics · Physics 2018-12-31 Mohammad Mahdi Salary , Samad Jafar-Zanjani , Hossein Mosallaei

While sensing in high temporal resolution is necessary for wide range of application, it is still limited nowadays due to cameras sampling rate. In this work we try to increase the temporal resolution beyond the Nyquist frequency, which is…

Signal Processing · Electrical Eng. & Systems 2022-11-28 Khen Cohen , Dan Raviv , David Mendlovic
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