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Title: Quantum state transfer in spin-1 chains

Abstract

We study the transfer of a quantum state through a Heisenberg spin-1 chain prepared in its ground state. We characterize the efficiency of the transfer via the fidelity of retrieving an arbitrarily prepared state and also via the transfer of quantum entanglement. The Heisenberg spin-1 chain has a very rich quantum phase diagram. We show that the boundaries of the different quantum phases are reflected in sharp variations of the transfer efficiency. In the vicinity of the border between the dimer and the ferromagnetic phase (in the conjectured spin-nematic region), we find strong indications for a qualitative change of the excitation spectrum. Moreover, we identify two regions of the phase diagram that give rise to particularly high transfer efficiency; the channel might be nonclassical even for chains of arbitrary length, in contrast to spin-1/2 chains.

Authors:
;  [1];  [1];  [2]
  1. Grup de Fisica Teorica, Departament de Fisica, Universitat Autonoma de Barcelona, E-08193 Bellaterra (Spain)
  2. (ICREA), E-08010 Barcelona (Spain)
Publication Date:
OSTI Identifier:
20982435
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.050303; (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; CHAINS; DIMERS; EFFICIENCY; EXCITATION; FERROMAGNETIC MATERIALS; GROUND STATES; HEISENBERG MODEL; PHASE DIAGRAMS; QUANTUM ENTANGLEMENT; QUANTUM MECHANICS; SPECTRA; SPIN; VARIATIONS

Citation Formats

Romero-Isart, O., Eckert, K., Sanpera, A., and Institucio Catalana de Recerca i Estudis Avancats. Quantum state transfer in spin-1 chains. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.050303.
Romero-Isart, O., Eckert, K., Sanpera, A., & Institucio Catalana de Recerca i Estudis Avancats. Quantum state transfer in spin-1 chains. United States. doi:10.1103/PHYSREVA.75.050303.
Romero-Isart, O., Eckert, K., Sanpera, A., and Institucio Catalana de Recerca i Estudis Avancats. Tue . "Quantum state transfer in spin-1 chains". United States. doi:10.1103/PHYSREVA.75.050303.
@article{osti_20982435,
title = {Quantum state transfer in spin-1 chains},
author = {Romero-Isart, O. and Eckert, K. and Sanpera, A. and Institucio Catalana de Recerca i Estudis Avancats},
abstractNote = {We study the transfer of a quantum state through a Heisenberg spin-1 chain prepared in its ground state. We characterize the efficiency of the transfer via the fidelity of retrieving an arbitrarily prepared state and also via the transfer of quantum entanglement. The Heisenberg spin-1 chain has a very rich quantum phase diagram. We show that the boundaries of the different quantum phases are reflected in sharp variations of the transfer efficiency. In the vicinity of the border between the dimer and the ferromagnetic phase (in the conjectured spin-nematic region), we find strong indications for a qualitative change of the excitation spectrum. Moreover, we identify two regions of the phase diagram that give rise to particularly high transfer efficiency; the channel might be nonclassical even for chains of arbitrary length, in contrast to spin-1/2 chains.},
doi = {10.1103/PHYSREVA.75.050303},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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