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In recent years, there has been growing interest in non-Hermitian phenomena in low-symmetry conductors, particularly optical gain driven by electro-optic effects. Conventional semiclassical treatments typically attribute these effects to…

Optics · Physics 2025-12-09 Sylvain Lannebère , Nader Engheta , Mário G. Silveirinha

We describe linear and nonlinear modes in a ring-shaped waveguide with localized gain and dissipation modeled by two Dirac $\delta$ functions located symmetrically. The strengths of the gain and dissipation are equal, i.e., the system obeys…

Pattern Formation and Solitons · Physics 2016-10-31 Dmitry A. Zezyulin , Vladimir V. Konotop

We develop a new fast-diffusion approximation for the kinetics of deposition of extended objects on a linear substrate, accompanied by diffusional relaxation. This new approximation plays the role of the mean-field theory for such processes…

Condensed Matter · Physics 2010-10-12 Vladimir Privman , Mustansir Barma

A generalized Landauer formula, derived with the methods due to Keldysh, and Baym and Kadanoff, is gaining widespread use in the modeling of transport in a large number of different mesoscopic systems. We review some of the recent…

Mesoscale and Nanoscale Physics · Physics 2017-08-23 Antti-Pekka Jauho

We establish asymptotic gain along with input-to-state practical stability results for disturbed semilinear systems w.r.t. the global attractor of the respective undisturbed system. We apply our results to a large class of nonlinear…

Analysis of PDEs · Mathematics 2020-10-21 Jochen Schmid , Oleksiy V. Kapustyan , Sergey Dashkovskiy

In this article, we study the effects of intrinsic nonlinear optomechanical interaction on the linear response of a driven-dissipative optomechanical system to a weak time-dependent perturbation. By calculating the linear response of the…

Quantum Physics · Physics 2025-02-17 B. Askari , A. Dalafi , M. J. Kazemi

A study on the effects of optical gain nonuniformly distributed in one-dimensional random systems is presented. It is demonstrated numerically that even without gain saturation and mode competition, the spatial nonuniformity of gain can…

Optics · Physics 2010-08-25 Jonathan Andreasen , Christian Vanneste , Li Ge , Hui Cao

Theory of light absorption and circular photocurrent in Weyl semimetals is developed for arbitrary large light intensities with account for both elastic and inelastic relaxation processes of Weyl fermions. The direct optical transition rate…

Mesoscale and Nanoscale Physics · Physics 2019-10-21 N. V. Leppenen , E. L. Ivchenko , L. E. Golub

A novel method for correcting the effect of nonlinear distortion in orthogonal frequency division multiplexing signals is proposed. The method depends on adaptively selecting the distortion over a subset of the data carriers, and then using…

Information Theory · Computer Science 2015-07-01 Ebrahim B. Al-Safadi , Tareq Y. Al-Naffouri , Mudassir Masood , Anum Ali

Diffusion is a fundamental physical phenomenon with critical applications in fields such as metallurgy, cell biology, and population dynamics. While standard diffusion is well-understood, anomalous diffusion often requires complex non-local…

Statistical Mechanics · Physics 2026-01-16 Gabriel Barreiro , Vladimir Pérez-Veloz

Media featuring both optical gain and disorder, such as random lasers, represent formidable challenges as subjects of research due to the high complexity of the light propagation within them; however, dramatic advances in this nascent field…

We study a chemotaxis-consumption mechanism, in which some chemical signal and cells density interact each other. In order to control the concentration of such a population, sources involving gradient nonlinearities, which introduce a…

Analysis of PDEs · Mathematics 2025-01-24 Daniel Acosta Soba , Alessandro Columbu , Giuseppe Viglialoro

An adaptive mesh refinement (AMR) scheme is implemented in a distributed environment using Message Passing Interface (MPI) to find solutions to the nonlinear sigma model. Previous work studied behavior similar to black hole critical…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Steven L. Liebling

Random media with tailored optical properties are attracting burgeoning interest for applications in imaging, biophysics, energy, nanomedicine, spectroscopy, cryptography and telecommunications. A key paradigm for devices based on this…

Optics · Physics 2019-01-15 A. Fleming , C. Conti , A. Di Falco

The peculiar characteristics of random laser emission have been studied in many different media, leading to a classification of the working regimes based on the statistics of spectral fluctuations. Alongside such studies, the possibility to…

Masked Diffusion Models (MDMs) enable flexible decoding orders, yet existing samplers remain largely greedy, selecting locally certain tokens without accounting for their downstream effects. We show that this myopia can increase cumulative…

Computation and Language · Computer Science 2026-05-25 Kaisen Yang , Jayden Teoh , Kaicheng Yang , Yitong Zhang , Alex Lamb

We consider the optical fiber channel modelled by the nonlinear Shr\"{o}dinger equation with zero dispersion and additive Gaussian noise. Using Feynman path-integral approach for the model we find corrections to conditional probability…

Information Theory · Computer Science 2017-01-25 A. A. Panarin , A. V. Reznichenko , I. S. Terekhov

Transparent media exhibiting anomalous dispersion have been of considerable interest since Wang, Kuzmich, and Dogariu [Nature {\bf 406}, 277 (2000)] first observed light propagate with superluminal and negative group velocities without…

Quantum Physics · Physics 2011-02-01 James Owen Weatherall , Christopher P. Search

Driven-dissipative systems have recently attracted great attention due to the existence of novel physical phenomena with no analog in the equilibrium case. The Keldysh path-integral theory is a powerful tool to investigate these systems.…

Quantum Physics · Physics 2021-01-04 Yuanwei Zhang , Gang Chen

A wideband Gaussian Noise Model of the nonlinear noise power spectral density is developed for a single semiconductor optical amplifier as described by the Agrawal model. A simple, interpretable closed-form expression is obtained for the…

Optics · Physics 2026-03-16 Hartmut Hafermann