Entanglement induced by a single-mode heat environment
TL;DR: In this article, the authors studied the interaction of the thermal field and a quantum system composed of two qubits and found that such a chaotic field with minimal information can nevertheless entangle the qubits which are prepared initially in a separable state.
Abstract: A thermal field, which frequently appears in problems of decoherence, provides us with minimal information about the field. We study the interaction of the thermal field and a quantum system composed of two qubits and find that such a chaotic field with minimal information can nevertheless entangle the qubits which are prepared initially in a separable state. This simple model of a quantum register interacting with a noisy environment allows us to understand how memory of the environment affects the state of a quantum register.
Citations
More filters
[...]
TL;DR: In this article, the basic aspects of entanglement including its characterization, detection, distillation, and quantification are discussed, and a basic role of entonglement in quantum communication within distant labs paradigm is discussed.
Abstract: All our former experience with application of quantum theory seems to say:
{\it what is predicted by quantum formalism must occur in laboratory} But the
essence of quantum formalism - entanglement, recognized by Einstein, Podolsky,
Rosen and Schr\"odinger - waited over 70 years to enter to laboratories as a
new resource as real as energy This holistic property of compound quantum systems, which involves
nonclassical correlations between subsystems, is a potential for many quantum
processes, including ``canonical'' ones: quantum cryptography, quantum
teleportation and dense coding However, it appeared that this new resource is
very complex and difficult to detect Being usually fragile to environment, it
is robust against conceptual and mathematical tools, the task of which is to
decipher its rich structure This article reviews basic aspects of entanglement including its
characterization, detection, distillation and quantifying In particular, the
authors discuss various manifestations of entanglement via Bell inequalities,
entropic inequalities, entanglement witnesses, quantum cryptography and point
out some interrelations They also discuss a basic role of entanglement in
quantum communication within distant labs paradigm and stress some
peculiarities such as irreversibility of entanglement manipulations including
its extremal form - bound entanglement phenomenon A basic role of entanglement
witnesses in detection of entanglement is emphasized
6,980 citations
TL;DR: It is shown that two, noninteracting two-level systems, immersed in a common bath, can become mutually entangled when evolving according to a Markovian, completely positive reduced dynamics.
Abstract: We show that two, noninteracting two-level systems, immersed in a common bath, can become mutually entangled when evolving according to a Markovian, completely positive reduced dynamics.
375 citations
TL;DR: In this paper, the authors present an overview of recent theoretical and experimental efforts to underpin the dynamics of entanglement in open quantum systems and survey how it evolves due to the interaction of the entangled system with its surroundings.
Abstract: One of the greatest challenges in quantum information processing is the coherent control over quantum systems with an ever increasing number of particles. Within this endeavor, the harnessing of many-body entanglement against the effects of the environment is a pressing issue. Besides being an important concept from a fundamental standpoint, entanglement is recognized as a crucial resource for performance enhancements over classical methods. Understanding and controlling many-body entanglement in open systems may have implications in quantum computing, quantum simulations, secure quantum communication, quantum metrology, our understanding of the quantum-to-classical transition, and other important questions of quantum foundations.
Here we present an overview of recent theoretical and experimental efforts to underpin the dynamics of entanglement in open quantum systems. Entanglement is taken as a dynamic quantity, and we survey how it evolves due to the interaction of the entangled system with its surroundings. We analyze several scenarios, corresponding to different families of states and environments, which render a diversity of dynamical behaviors.
Contrary to single-particle quantities, that typically vanish only asymptotically in time, entanglement may disappear at a finite time. Moreover, important classes of entanglement show an exponential decay with the system size when subject to local noise, posing yet another threat to the already challenging scaling of quantum technologies. Results for the local and global noise cases are summarized. Robustness-enhancement techniques, scaling laws, statistical and geometrical aspects of multipartite-entanglement decay are also reviewed; all in order to give a broad picture of entanglement dynamics in open quantum systems addressed to both theorists and experimentalists inside and outside the field of quantum information.
298 citations
TL;DR: An overview of recent theoretical and experimental efforts to underpin the dynamics of entanglement under the influence of noise is presented, and how it evolves due to the unavoidable interaction of the entangled system with its surroundings is surveyed.
Abstract: One of the greatest challenges in the fields of quantum information processing and quantum technologies is the detailed coherent control over each and every constituent of quantum systems with an ever increasing number of particles. Within this endeavor, harnessing of many-body entanglement against the detrimental effects of the environment is a major pressing issue. Besides being an important concept from a fundamental standpoint, entanglement has been recognized as a crucial resource for quantum speed-ups or performance enhancements over classical methods. Understanding and controlling many-body entanglement in open systems may have strong implications in quantum computing, quantum simulations of many-body systems, secure quantum communication or cryptography, quantum metrology, our understanding of the quantum-to-classical transition, and other important questions of quantum foundations.In this paper we present an overview of recent theoretical and experimental efforts to underpin the dynamics of entanglement under the influence of noise. Entanglement is thus taken as a dynamic quantity on its own, and we survey how it evolves due to the unavoidable interaction of the entangled system with its surroundings. We analyze several scenarios, corresponding to different families of states and environments, which render a very rich diversity of dynamical behaviors.In contrast to single-particle quantities, like populations and coherences, which typically vanish only asymptotically in time, entanglement may disappear at a finite time. In addition, important classes of entanglement display an exponential decay with the number of particles when subject to local noise, which poses yet another threat to the already-challenging scaling of quantum technologies. Other classes, however, turn out to be extremely robust against local noise. Theoretical results and recent experiments regarding the difference between local and global decoherence are summarized. Control and robustness-enhancement techniques, scaling laws, statistical and geometrical aspects of multipartite-entanglement decay are also reviewed; all in order to give a broad picture of entanglement dynamics in open quantum systems addressed to both theorists and experimentalists inside and outside the field of quantum information.
236 citations
Cites background from "Entanglement induced by a single-mo..."
...Entanglement between two non-interacting qubits can be created by interaction with a common environment [149, 174–176], even when this environment is in a thermal state [174, 175]....
[...]
[...]
TL;DR: In this article, the authors introduce the essential concepts and the mathematical formalism of decoherence, focusing on the picture of the decoding process as a continuous monitoring of a quantum system by its environment.
Abstract: Quantum decoherence plays a pivotal role in the dynamical description of the quantum-to-classical transition and is the main impediment to the realization of devices for quantum information processing. This paper gives an overview of the theory and experimental observation of the decoherence mechanism. We introduce the essential concepts and the mathematical formalism of decoherence, focusing on the picture of the decoherence process as a continuous monitoring of a quantum system by its environment. We review several classes of decoherence models and discuss the description of the decoherence dynamics in terms of master equations. We survey methods for avoiding and mitigating decoherence and give an overview of several experiments that have studied decoherence processes. We also comment on the role decoherence may play in interpretations of quantum mechanics and in addressing foundational questions.
169 citations
References
More filters
Book•
01 Jan 2000
TL;DR: In this article, the quantum Fourier transform and its application in quantum information theory is discussed, and distance measures for quantum information are defined. And quantum error-correction and entropy and information are discussed.
Abstract: Part I Fundamental Concepts: 1 Introduction and overview 2 Introduction to quantum mechanics 3 Introduction to computer science Part II Quantum Computation: 4 Quantum circuits 5 The quantum Fourier transform and its application 6 Quantum search algorithms 7 Quantum computers: physical realization Part III Quantum Information: 8 Quantum noise and quantum operations 9 Distance measures for quantum information 10 Quantum error-correction 11 Entropy and information 12 Quantum information theory Appendices References Index
25,929 citations