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Title: Controlled quantum-state transfer in a spin chain

Abstract

Control of the transfer of quantum information encoded in quantum wave packets moving along a spin chain is demonstrated. Specifically, based on a relationship with control in a paradigm of quantum chaos, it is shown that wave packets with slow dispersion can automatically emerge from a class of initial superposition states involving only a few spins, and that arbitrary unspecified traveling wave packets can be nondestructively stopped and later relaunched with perfection. The results establish an interesting application of quantum chaos studies in quantum information science.

Authors:
 [1];  [2]
  1. Department of Physics and Center for Computational Science and Engineering, National University of Singapore, 117542 (Singapore)
  2. Chemical Physics Theory Group and Center for Quantum Information and Quantum Control, University of Toronto, Toronto M5S 3H6 (Canada)
Publication Date:
OSTI Identifier:
20982277
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 3; Other Information: DOI: 10.1103/PhysRevA.75.032331; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CHAOS THEORY; COMMUNICATIONS; CONTROL THEORY; INFORMATION THEORY; QUANTUM CRYPTOGRAPHY; QUANTUM INFORMATION; QUANTUM MECHANICS; SPIN; TRAVELLING WAVES; WAVE PACKETS

Citation Formats

Gong, Jiangbin, and Brumer, Paul. Controlled quantum-state transfer in a spin chain. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.032331.
Gong, Jiangbin, & Brumer, Paul. Controlled quantum-state transfer in a spin chain. United States. doi:10.1103/PHYSREVA.75.032331.
Gong, Jiangbin, and Brumer, Paul. Thu . "Controlled quantum-state transfer in a spin chain". United States. doi:10.1103/PHYSREVA.75.032331.
@article{osti_20982277,
title = {Controlled quantum-state transfer in a spin chain},
author = {Gong, Jiangbin and Brumer, Paul},
abstractNote = {Control of the transfer of quantum information encoded in quantum wave packets moving along a spin chain is demonstrated. Specifically, based on a relationship with control in a paradigm of quantum chaos, it is shown that wave packets with slow dispersion can automatically emerge from a class of initial superposition states involving only a few spins, and that arbitrary unspecified traveling wave packets can be nondestructively stopped and later relaunched with perfection. The results establish an interesting application of quantum chaos studies in quantum information science.},
doi = {10.1103/PHYSREVA.75.032331},
journal = {Physical Review. A},
number = 3,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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