Decoherence, Entanglement and Information Protection in Complex Quantum Systems: Proceedings of the NATO ARW on Decoherence, Entanglement and Information Protection in Complex Quantum Systems, Les Houches, France, from 26 to 30 April 2004.

by Vladimir M. Akulin (Editor), A. Sarfati (Editor), G. Kurizki (Editor), S. Pellegrin (Editor)

Overview

Dynamics of an open system interacting with theenvironment considered as a thermostate may be formulatedin terms of a master equation with an integral operator allowing for the relaxation process, [Zwanzig 1960]. In some part- ular cases this operator hasashort-lastingkernel that enables one to consider therelaxation as a Markovian process and to obtainthe master equation inthe Lindblad form, [Lindblad 1976 (a)]. In some situations the memory effects become, however, important and the dynamics of thesystem gets much more involved, [Barnett 2001]. A similar situation arises inthe case where a set of consecutive or continuous measurements is performed. The purpose of this article is to consider a situation where some simplification of the generalform of the master equation with memory isstill possibleand the result isasimpler master equation. In particular, we consider the case of a dynamic system c- pled to a measured ancilla via a nondemolition interaction, [Caves 1980]. This simplifies the consideration essentiallywhereas providing an important special case inwhich the energy of the dynamic part is conserved. We consider a composite quantum system consisting of a dynamic part - teracting with an ancillary part, the latter being subject to repeated projective measurements. The entire quantum system is assumed to evolve unitarily d- ing time ? t between the measurements. As a specific example, we analyze a harmonic oscillator coupledtoatwo-level ancillathat issubject to measu- ments.

Product Details

ISBN-13:	9781402032820
Publisher:	Springer Netherlands
Publication date:	09/16/2005
Series:	NATO Science Series II: Mathematics, Physics and Chemistry , #189
Edition description:	2005
Pages:	704
Product dimensions:	8.50(w) x 10.98(h) x (d)

Table of Contents

Editorial Article.- Role of Entanglement in Quantum Computing and Information Processing.- Quantum Ensembles and Quantum Informatics.- Entanglement in Quantum Information Processing.- Easy Control Over Fermionic Computations.- Multiatom and Multiphoton Entanglement.- Multiatom and Multiphoton Entanglement.- On the Advanced Wave Model of Parametric Down-Conversion.- Quantum Logics Based on Four-Photon Entanglement.- Towards Quantum Control of Light: Shaping Quantum Pulses of Light via Coherent Atomic Memory.- Deterministic Entanglement of Single Photons via Coherently Driven Atoms.- Selective Control of High-Order Atomic Coherences.- Strong Entanglement of Bright Light Beams in Controlled Quantum Systems.- Adiabatic and Nonadiabatic Protection from Decoherence.- Adiabatic and Nonadiabatic Protection from Decoherence.- Coherence Protection by the Quantum Zeno Effect.- Possible Implementation of Topologically Protected Qubits by a Novel Class of Josephson Junction Arrays.- Coherence Protection Near Energy Gaps.- Zeno and Anti-Zeno Dynamics.- Non-Markovian Decay and Decoherence in Open Quantum Systems.- Non-Markovian Decay and Decoherence in Open Quantum Systems.- The Varieties of Master Equations.- Quantum Dynamics Effected by Repeated Measurements.- Non-Exponential Motional Damping of Impurity Atoms in Bose-Einstein Condensates.- Internal-Translational Entanglement and Interference in Atoms and Molecules.- Internal-Translational Entanglement and Interference in Atoms and Molecules.- Atom-Mesoscopic Field Entanglement.- Coherence and Decoherence Experiments with Fullerenes.- Distant Entanglement of Macroscopic Gas Samples.- Position and Momentum Entanglement of Dipole-Dipole Interacting Atoms in Optical Lattices.- Investigation of Autler-Townes Effect in Sodium Dimers.- Transition Steering via Space-Dependent Coupling.- Coherence and Decoherence in Rydberg Gases.- Proton Entanglement and Decoherence in Solids.- Schrödinger’s Cat States of Protons in Condensed Matter.- Anomalous Neutron Inelastic Cross Sections at eV Energy Transfers.- Quantum Entanglement and Decoherence Due to Coupling of Protons to Electronic Environment.- Attosecond Effects in Scattering of Neutrons and Electrons from Protons.- Macroscopic Quantum Entanglement in the KHCO3 Crystal.- Probing Short-Lived Entanglement with Inelastic X-ray Scattering.- Proton-Proton Correlations in Condensed Matter.- Is Fermi’s Golden Rule Always True for Compton Scattering?.- On Correlation Approach to Scattering in the Decoherence Timescale.- Coherence and Entanglement in Mesoscopic Systems.- Coherence and Entanglement in Mesoscopic Systems.- Probe Scattering by Fluctuating Multi-Atom Ensembles in Optical Lattices.- Bose-Einstein Condensates with Laser-Induced Dipole-Dipole Interactions.- Atom Optics with Bose-Einstein Condensation Using Optical Potentials.- A Mesoscopic Mach-Zehnder Interferometer.- Coherent Transport by Adiabatic Pumping.- Zeno and Anti-Zeno Effects in Driven Josephson Junctions: Control of Macroscopic Quantum Tunneling.- Employment of Submicron YBA2CU3O7-x Grain Boundary Junctions for the Fabrication of “ Quiet” Superconducting Flux-Qubits.- Broken Symmetry and Coherence of Molecular Vibrations in Tunnel Transitions.