English
Related papers

Related papers: Beyond the Rozanov Bound on Electromagnetic Absorp…

200 papers

In this study, we experimentally investigate the application of a transient signal with complex frequencies to the absorption and transmission of sound waves. Indeed, the emission of a wave with an exponentially varying amplitude in time is…

Applied Physics · Physics 2025-03-18 Anis Maddi , Gaelle Poignand , Vassos Achilleos , Vincent Pagneux , Guillaume Penelet

The problem of reconstructing the spatial support of an extended radiating electric current source density in a lossy dielectric medium from transient boundary measurements of the electric fields is studied. A time reversal algorithm is…

Mathematical Physics · Physics 2014-09-19 Abdul Wahab , Amer Rasheed , Tasawar Hayat , Rab Nawaz

We derive fundamental per-channel bounds on angle-integrated absorption and thermal radiation for arbitrary bodies---for any given material susceptibility and bounding region---that simultaneously encode both the per-volume limit on…

Achieving non-reciprocity and building nonreciprocal components through spatio-temporal modulation of material properties has attracted a lot of attention in the recent past as an alternative to the more traditional approach of exploiting…

Applied Physics · Physics 2018-10-31 Negar Reiskarimian , Aravind Nagulu , Tolga Dinc , Harish Krishnaswamy

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

Time-reversal symmetry breaking (TRSB) has been central to detecting exotic phases of matter. Here, we leverage the circuit electrodynamics capabilities of superconducting devices to propose a novel scheme based on a multimode…

This paper introduces temporal Bragg gratings as a new class of broadband, reconfigurable parametric amplifiers. We present a comprehensive investigation of power amplification in temporal Bragg gratings, spatially periodic structures with…

Optics · Physics 2026-04-15 Sajjad Taravati

We demonstrate an efficient double-layer light absorber by exciting plasmonic phase resonances. We show that the addition of grooves can cause mode splitting of the plasmonic waveguide cavity modes and all the new resonant modes exhibit…

Optics · Physics 2010-07-30 Yanxia Cui , Kin Hung Fung , Jun Xu , Sailing He , Nicholas X. Fang

Time-varying networks, consisting of lumped elements, such as resistors, capacitors, and inductors, actively modulated in time, have introduced a host of novel wave phenomena and witnessed a remarkable development during recent years. This…

We theoretically study the propagation through a resonant absorbing medium of a time-dependent perturbation modulating the amplitude of a continuous wave (cw). Modeling the medium as a system of two-level atoms and linearizing the…

Optics · Physics 2010-09-13 Bruno Macke , Bernard Ségard

The transfer matrix method remains a simple yet powerful tool for modeling acoustic systems, particularly in a closed waveguide geometry. Here we present a generalisation of this method based on the theory of mode matching, that…

Applied Physics · Physics 2025-04-07 D. Cidlinsky , G. J. Chaplain , S. A. R. Horsley

We derive and discuss general physical bounds on the electromagnetic scattering and absorption of passive structures. Our theory, based on passivity and power conservation, quantifies the minimum and maximum allowed scattering for an object…

Optics · Physics 2015-06-17 Romain Fleury , Jason Soric , Andrea Alu

Here we discuss the physics of electro-optic modulators deploying 2D materials. We include a scaling laws analysis showing how energy-efficiency and speed change for three underlying cavity systems as a function of critical device length…

Mesoscale and Nanoscale Physics · Physics 2018-02-14 Zhizhen Ma , Rohit Hemnani , Ludwig Bartels , Ritesh Agarwal , Volker J. Sorger

Epsilon-near-zero (ENZ) systems exhibit unconventional electromagnetic response close to their zero permittivity regime. Here, we explore the ability of ultrathin ENZ films to modulate the transmission of radiation from an underlying…

Optics · Physics 2026-03-04 Arun Mambra , Ravi Pant , Joy Mitra

Periodically time-varying media, known as photonic time crystals (PTCs), provide a promising platform for observing unconventional wave phenomena. We analyze the scattering of electromagnetic waves from spatially finite PTCs using the…

This letter proposes a new time domain absorption approach designed to reduce masking components of speech signals under noisy-reverberant conditions. In this method, the non-stationarity of corrupted signal segments is used to detect…

Audio and Speech Processing · Electrical Eng. & Systems 2020-02-19 G. Zucatelli , R. Coelho

We investigate the optical response of a conduction electron in a helically twisted mesoscopic medium containing a screw dislocation and a uniform torsional background, in the presence of an axial magnetic field and an Aharonov--Bohm flux.…

Mesoscale and Nanoscale Physics · Physics 2026-04-15 Carlos Magno O. Pereira , Edilberto O Silva

We report on new electromagnetic modes in space-time modulated dispersion-engineered media. These modes exhibit unusual dispersion relation, field profile and scattering properties. They are generated by coupled codirectional space-time…

The temporal modulation of material parameters enables optical amplification within linear media. Here we consider the fundamental building block of plasmonics, a subwavelength metal nanoparticle, and study how temporal modulation alters…

Mesoscale and Nanoscale Physics · Physics 2025-08-29 Miguel Verde , Paloma A. Huidobro

Complex absorbing potentials (CAPs) are artificial potentials added to electronic Hamiltonians to make the wavefunction of metastable electronic states square-integrable. This makes the electronic structure problem of electronic resonances…

Chemical Physics · Physics 2022-11-29 Jerryman A. Gyamfi , Thomas -C. Jagau