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Title: Quantum state swapping via a qubit network with Hubbard interactions

Abstract

We study the quantum state transfer (QST) in a class of qubit networks with on-site Coulomb interaction, which are described by the generalized Hubbard model with engineered hopping strengths. It is proved that the N-site system of two electrons with opposite spins can be rigorously reduced into N one dimensional engineered single Bloch electron models with central potential barrier. With this observation, we find that such system can perform a perfect QST, the quantum swapping between two distant electrons with opposite spins. Numerical results show that such QST and the resonant tunneling occur for the optimal on-site repulsive interaction.

Authors:
; ;  [1];  [2]
  1. Department of Physics, Nankai University, Tianjin 300071 (China)
  2. (China)
Publication Date:
OSTI Identifier:
20788185
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 19; Other Information: DOI: 10.1103/PhysRevB.73.195122; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CENTRAL POTENTIAL; ELECTRONS; HUBBARD MODEL; ONE-DIMENSIONAL CALCULATIONS; QUANTUM COMPUTERS; QUBITS; SPIN; TUNNEL EFFECT

Citation Formats

Yang, S., Song, Z., Sun, C. P., and Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China and Department of Physics, Nankai University, Tianjin 300071. Quantum state swapping via a qubit network with Hubbard interactions. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.1.
Yang, S., Song, Z., Sun, C. P., & Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China and Department of Physics, Nankai University, Tianjin 300071. Quantum state swapping via a qubit network with Hubbard interactions. United States. doi:10.1103/PHYSREVB.73.1.
Yang, S., Song, Z., Sun, C. P., and Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China and Department of Physics, Nankai University, Tianjin 300071. Mon . "Quantum state swapping via a qubit network with Hubbard interactions". United States. doi:10.1103/PHYSREVB.73.1.
@article{osti_20788185,
title = {Quantum state swapping via a qubit network with Hubbard interactions},
author = {Yang, S. and Song, Z. and Sun, C. P. and Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, China and Department of Physics, Nankai University, Tianjin 300071},
abstractNote = {We study the quantum state transfer (QST) in a class of qubit networks with on-site Coulomb interaction, which are described by the generalized Hubbard model with engineered hopping strengths. It is proved that the N-site system of two electrons with opposite spins can be rigorously reduced into N one dimensional engineered single Bloch electron models with central potential barrier. With this observation, we find that such system can perform a perfect QST, the quantum swapping between two distant electrons with opposite spins. Numerical results show that such QST and the resonant tunneling occur for the optimal on-site repulsive interaction.},
doi = {10.1103/PHYSREVB.73.1},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 19,
volume = 73,
place = {United States},
year = {Mon May 15 00:00:00 EDT 2006},
month = {Mon May 15 00:00:00 EDT 2006}
}
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