scispace - formally typeset
Search or ask a question
Topic

Master equation

About: Master equation is a research topic. Over the lifetime, 10541 publications have been published within this topic receiving 276095 citations.


Papers
More filters
Journal ArticleDOI
01 Jul 2020
TL;DR: In this paper, a broad overview of the recent progress in the field of quantum electrodynamics in the ultrastrong-coupling regime is presented, ranging from analytical estimate of ground-state properties to proper derivations of master equations and computation of photodetection signals.
Abstract: This article reviews theoretical methods developed in the last decade to understand cavity quantum electrodynamics in the ultrastrong-coupling regime, where the strength of the light-matter interaction becomes comparable to the photon frequency. Along with profound modifications of fundamental quantum optical effects giving rise to a rich phenomenology, this regime introduces significant theoretical challenges. One of the most important is the break-down of the rotating-wave approximation which neglects all non-resonant terms in light-matter interaction Hamiltonians. Consequently, a large part of the quantum optical theoretical framework has to be revisited in order to accurately account for all interaction terms in this regime. We give in this article a broad overview of the recent progress, ranging from analytical estimate of ground-state properties to proper derivations of master equations and computation of photodetection signals. For each aspect of the theory, the basic principles of the methods are illustrated on paradigmatic models such as quantum Rabi and spin-boson models. In this spirit, most of the article is devoted to effective models, relevant for the various experimental platforms in which the ultrastrong coupling has been reached, such as semiconductor microcavities and superconducting circuits. The validity of these models is discussed in the last part of the article, where we address recent debates on fundamental issues related to gauge invariance in the ultrastrong-coupling regime.

72 citations

Journal ArticleDOI
TL;DR: It is concluded that multilevel phaseonium fuel can be utilized to overcome the decoherence in available systems and bring the photonic Carnot engines much closer to the capabilities of current resonator technologies.
Abstract: We investigate scaling of work and efficiency of a photonic Carnot engine with a number of quantum coherent resources. Specifically, we consider a generalization of the "phaseonium fuel" for the photonic Carnot engine, which was first introduced as a three-level atom with two lower states in a quantum coherent superposition by M. O. Scully, M. Suhail Zubairy, G. S. Agarwal, and H. Walther [Science 299, 862 (2003)SCIEAS0036-807510.1126/science.1078955], to the case of N+1 level atoms with N coherent lower levels. We take into account atomic relaxation and dephasing as well as the cavity loss and derive a coarse-grained master equation to evaluate the work and efficiency analytically. Analytical results are verified by microscopic numerical examination of the thermalization dynamics. We find that efficiency and work scale quadratically with the number of quantum coherent levels. Quantum coherence boost to the specific energy (work output per unit mass of the resource) is a profound fundamental difference of quantum fuel from classical resources. We consider typical modern resonator set ups and conclude that multilevel phaseonium fuel can be utilized to overcome the decoherence in available systems. Preparation of the atomic coherences and the associated cost of coherence are analyzed and the engine operation within the bounds of the second law is verified. Our results bring the photonic Carnot engines much closer to the capabilities of current resonator technologies.

72 citations

Book
27 Nov 2014
TL;DR: Random Variables as mentioned in this paper, Sequence of Independent Variables, Langevin equation, Fokker-Planck Equation I., Fokkersplanck Equations II, Markov Chains, and Master Equations I and II.
Abstract: Random Variables.- Sequence of Independent Variables.- Langevin equation.- Fokker-Planck Equation I.- Fokker-Planck Equation II.- Markov Chains.- Master Equation I.- Master Equation II.- Phase Transitions and Criticality.- Reactive Systems.- Glauber Model.- Systems with Inversion Symmetry.- Systems with Absorbing States.- Population Dynamics.- Probabilistic Cellular automata.- Reaction-Diffusion Processes.- Random Sequential Adsoprtion.- Percolation.

72 citations

Journal ArticleDOI
TL;DR: It is demonstrated that substantial coherence is retained when such light interacts with a two-photon-absorbing reservoir and is responsible for the preservation of squeezing in the steady state despite the effect of dissipation.
Abstract: We investigate the dynamical evolution of nonclassical states of light undergoing a two-photon absorption process. We consider two distinct cases of initial states, a squeezed coherent state and an eigenstate of the two-photon annihilation operator (a superposition of macroscopically distinct coherent states). We analyze the fluctuations in the photon-number operator and in the quadrature components of the field. Whereas one-photon linear damping rapidly destroys quantum features such as squeezing, we demonstrate that substantial coherence is retained when such light interacts with a two-photon-absorbing reservoir. This surviving coherence is responsible for the preservation of squeezing in the steady state despite the effect of dissipation. We relate the origin of squeezing of initially unsqueezed light interacting with two-photon absorbers with the squeezing generated by simple superposition states of light.

72 citations

Journal ArticleDOI
TL;DR: In this article, the non-equilibrium Anderson impurity model is solved to an unprecedented accuracy to obtain its spectral properties in the steady state using a recently developed approach, and the spectral properties of the nonequilibrium model are obtained using a spectral graph.
Abstract: The non-equilibrium Anderson impurity model is solved to an unprecedented accuracy to obtain its spectral properties in the steady state using a recently developed approach.

72 citations


Network Information
Related Topics (5)
Quantum
60K papers, 1.2M citations
94% related
Hamiltonian (quantum mechanics)
48.6K papers, 1M citations
94% related
Ground state
70K papers, 1.5M citations
92% related
Phase transition
82.8K papers, 1.6M citations
89% related
Excited state
102.2K papers, 2.2M citations
87% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023140
2022344
2021431
2020460
2019420
2018427