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An asymmetric exclusion process comprising positive particles, negative particles and vacancies is introduced. The model is defined on a ring and the dynamics does not conserve the number of particles. We solve the steady state exactly and…

Statistical Mechanics · Physics 2009-11-07 M. R. Evans , Y. Kafri , E. Levine , D. Mukamel

An inversionless gain of anti-Stokes radiation above the oscillation threshold in an optically-dense far-from-degenerate double-Lambda Doppler-broadened medium accompanied by Stokes gain is predicted. The outcomes are illustrated with…

Quantum Physics · Physics 2009-11-06 Thomas F. George , A. K. Popov

We implement and experimentally demonstrate a 60 GHz distributed system leveraging an optical time synchronization system that provides precise time and frequency alignment between independent elements of the distributed mesh. Utilizing…

Quantum optical techniques may yield immersion fluids with high indices of refraction without absorption. We describe one such technique in which a probe field experiences a large index of refraction with amplification rather than…

The grid-following and grid-forming controls in voltage-source converters are considered as different operation modes and the synchronization mechanism of them are studied separately. In this article, the intrinsic relationships between…

Systems and Control · Electrical Eng. & Systems 2022-07-08 Kaizhe Zhang

We consider the problem of zeroing an error output of a nonlinear discrete-time system in the presence of constant exogenous disturbances, subject to hard convex constraints on the input signal. The design specification is formulated as a…

Optimization and Control · Mathematics 2021-05-07 John W. Simpson-Porco

Optical gain is a critical process in today's semiconductor technology and it is most often achieved via stimulated emission. In this theoretical study, we find a resonant TE mode in biased low-symmetry two-dimensional metallic systems…

Mesoscale and Nanoscale Physics · Physics 2025-10-30 N. Roldan-Levchenko , D. J. P. de Sousa , C. O. Ascencio , J. D. S Forte , L. Martin-Moreno , T. Low

We design fast bias inversions of an asymmetric double well so that the lowest states in each well remain so and free from residual motional excitation. This cannot be done adiabatically, and a sudden bias switch produces in general…

Quantum Physics · Physics 2015-11-11 S. Martínez-Garaot , M. Palmero , D. Guéry-Odelin , J. G. Muga

Thouless pumping is an emblematic manifestation of topology in physics, referring to the ability to induce a quantized transport of charge across a system by simply varying one of its parameters periodically in time. The original concept of…

Mesoscale and Nanoscale Physics · Physics 2025-03-31 S. Ravets , N. Pernet , N. Mostaan , N. Goldman , J. Bloch

We demonstrate two techniques for studying the features of three-level systems driven by two lasers (called control and probe), when the transitions are Doppler broadened as in room-temperature vapor. For $\Lambda$-type systems, the probe…

Optics · Physics 2007-05-23 Umakant D. Rapol , Vasant Natarajan

This paper considers the dynamic response of a single degree of freedom system with nonlinear stiffness and nonlinear damping that is subjected to both resonant direct excitation and resonant parametric excitation, with a general phase…

Mesoscale and Nanoscale Physics · Physics 2020-11-03 Donghao Li , Steven W. Shaw

A Thouless pump can be regarded as a dynamical version of the integer quantum Hall effect. In a finite-size configuration, such topological pump displays edge modes that emerge dynamically from one bulk-band and dive into the opposite…

Mesoscale and Nanoscale Physics · Physics 2020-11-24 Wenting Cheng , Emil Prodan , Camelia Prodan

Relaxed conditions are given for stability of a feedback system consisting of an exponentially stable multi-input multi-output nonlinear plant and an integral controller. Roughly speaking, it is shown that if the composition of the plant…

Optimization and Control · Mathematics 2020-08-24 John W. Simpson-Porco

This research sets forth a universal framework to characterize the beamforming gain achievable with arbitrarily nonideal phase shifters. Precisely, the maximum possible shortfall relative to the gain attainable with ideal phase shifters is…

Signal Processing · Electrical Eng. & Systems 2026-01-15 Heedong Do , Angel Lozano

We present a general theory of gain-modified emission dynamics between two quantum emitters (two level systems) in a linear gain medium, demonstrating how gain modifies the usual radiative decay rates and inter-emitter coupling and decay…

Quantum Physics · Physics 2025-09-23 Becca VanDrunen , Juanjuan Ren , Sebastian Franke , Stephen Hughes

A method is proposed for preparing any pure and a wide class of mixed quantum states in the decoherence-free ground-state subspace of a degenerate multilevel lambda system. The scheme is a combination of optical pumping and a series of…

Quantum Physics · Physics 2009-11-10 Attila Karpati , Zsolt Kis , Peter Adam

Nonlinear interaction enables topological phenomena impossible in linear systems. A paradigm is nonlinear Thouless pump, where the transport of solitons can be topologically quantized even when band occupation is nonuniform. Such nonlinear…

Quantum Gases · Physics 2026-04-01 Xuzhen Cao , Xiaolin Li , Liang Bai , Zhaoxin Liang , Li-Chen Zhao , Ying Hu

We present a description of a strongly driven multimode optomechanical system that shows the emergence of cooperative effects usually known from systems of atom-light interaction. Our calculations show that under application of a coherent…

Quantum Physics · Physics 2014-11-11 T. Kipf , G. S. Agarwal

We study the problem of driving an unknown initial mixed quantum state onto a known pure state without using unitary transformations. This can be achieved, in an efficient manner, with the help of sequential measurements on at least two…

Quantum Physics · Physics 2009-11-11 L. Roa , G. Olivares

Thouless pumps are time-periodic one-dimensional systems that capture the physics of the two-dimensional quantum Hall effect via the quantized pumping of particles under adiabatic modulation. Recent work in photonics has shown that…

Pattern Formation and Solitons · Physics 2025-02-21 Marius Jürgensen , Mikael C. Rechtsman