Quantum-information engines with many-body states attaining optimal extractable work with quantum control

In recent years, tools from quantum information theory have become indispensable in characterizing many-body systems. In this work, we employ measures of entanglement to study the interplay between disorder and the topological phase in 1D systems of the Kitaev type, which can host Majorana end modes at their edges. We find that the entanglement entropy may actually increase as a result of disorder, and identify the origin of this behavior in the appearance of an infinite-disorder critical point. We also employ the entanglement spectrum to accurately determine the phase diagram of the system, and find that disorder may enhance the topological phase, and lead to the appearance of Majorana zero modes in systems whose clean version is trivial.

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Macroscopic quantum control of exact many-body coherent states

The European Physical Journal D ◽

10.1140/epjd/e2010-10523-2 ◽

2010 ◽

Vol 61 (2) ◽

pp. 431-435 ◽

Cited By ~ 5

Author(s):

W. H. Hai ◽

Q. Xie ◽

S. G. Rong

Keyword(s):

Coherent States ◽

Quantum Control ◽

Many Body ◽

Macroscopic Quantum

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Many-Body Physics from a Quantum Information Perspective

Modern Theories of Many-Particle Systems in Condensed Matter Physics - Lecture Notes in Physics ◽

10.1007/978-3-642-10449-7_6 ◽

2012 ◽

pp. 245-294 ◽

Cited By ~ 8

Author(s):

R. Augusiak ◽

F. M. Cucchietti ◽

M. Lewenstein

Keyword(s):

Quantum Information ◽

Many Body ◽

Many Body Physics

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Phase control for entanglement preparation in two-qubit systems

Quantum Information and Computation ◽

10.26421/qic5.45-7 ◽

2005 ◽

Vol 5 (4&5) ◽

pp. 364-379

Author(s):

V.S. Malinovsky ◽

I.R. Sola

Keyword(s):

Quantum Information ◽

Quantum Computation ◽

Quantum Control ◽

Phase Control ◽

Adiabatic Passage ◽

Pulse Parameters ◽

Qubit System ◽

Phase Manipulation ◽

Laser Control ◽

Pi Pulses

The theory of Quantum Control is starting to lay bridges with the field of Quantum Information and Quantum Computation. Using key ideas of laser control of the dynamics by means of phase manipulation and adiabatic passage, we review laser schemes that allow entanglement preparation in a two-qubit system. The schemes are based on sequences that use four time-delayed pulses, with or without concerted decay, in or off resonance with the intermediate levels of the qubit space. We show how to control the fidelity and phase of the entanglement, as well as the sensitivity of the preparation to the different pulse parameters. In general the schemes provide an improvement in robustness and in the finesse of the control to phase, with respect to previously proposed schemes based on sequences of $\pi$ pulses.

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Five Lectures on Quantum Information Applications of Complex Many-Body Systems

Lecture Notes in Physics - Theoretical Foundations of Quantum Information Processing and Communication ◽

10.1007/978-3-642-02871-7_4 ◽

2009 ◽

pp. 97-124

Author(s):

Sougato Bose

Keyword(s):

Quantum Information ◽

Many Body ◽

Many Body Systems

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FERMIONIC QUANTUM MANY-BODY SYSTEMS: A QUANTUM INFORMATION APPROACH

Complex Quantum Systems - Lecture Notes Series, Institute for Mathematical Sciences, National University of Singapore ◽

10.1142/9789814460156_0006 ◽

2013 ◽

pp. 195-217

Author(s):

Christina V. Kraus

Keyword(s):

Quantum Information ◽

Many Body ◽

Information Approach ◽

Many Body Systems

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Unification of the Nature’s Complexities via a Matrix Permanent—Critical Phenomena, Fractals, Quantum Computing, ♯P-Complexity

Entropy ◽

10.3390/e22030322 ◽

2020 ◽

Vol 22 (3) ◽

pp. 322

Author(s):

Vitaly Kocharovsky ◽

Vladimir Kocharovsky ◽

Sergey Tarasov

Keyword(s):

Quantum Computing ◽

Quantum Information ◽

Computational Complexity ◽

Critical Phenomena ◽

Complex Variables ◽

Integral Representations ◽

Many Body ◽

Fractal Structures ◽

Information Processes ◽

Complete Problems

We reveal the analytic relations between a matrix permanent and major nature’s complexities manifested in critical phenomena, fractal structures and chaos, quantum information processes in many-body physics, number-theoretic complexity in mathematics, and ♯P-complete problems in the theory of computational complexity. They follow from a reduction of the Ising model of critical phenomena to the permanent and four integral representations of the permanent based on (i) the fractal Weierstrass-like functions, (ii) polynomials of complex variables, (iii) Laplace integral, and (iv) MacMahon master theorem.

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