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Title: Bosonization study of quantum phase transitions in the one-dimensional asymmetric Hubbard model

Abstract

The quantum phase transitions in the one-dimensional asymmetric Hubbard model are investigated with the bosonization approach. The conditions for the phase transition from density wave to phase separation, the correlation functions, and their exponents are obtained analytically. Our results show that the difference between the hopping integrals for up- and down-spin electrons is crucial for the occurrence of the phase separation. When the difference is large enough, the phase separation will appear even if the on-site interaction is small.

Authors:
 [1];  [2];  [1];  [3]
  1. Department of Physics, Tongji University, Shanghai 200092 (China)
  2. (China)
  3. Department of Physics and the Institute of Theoretical Physics, Chinese University of Hong Kong, Hong Kong (China)
Publication Date:
OSTI Identifier:
20957817
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 75; Journal Issue: 16; Other Information: DOI: 10.1103/PhysRevB.75.165111; (c) 2007 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; ASYMMETRY; BOSON EXPANSION; CHARGE DENSITY; CORRELATION FUNCTIONS; DENSITY; ELECTRONS; HUBBARD MODEL; INTEGRALS; ONE-DIMENSIONAL CALCULATIONS; PHASE TRANSFORMATIONS; SPIN

Citation Formats

Wang, Z. G., Department of Physics and the Institute of Theoretical Physics, Chinese University of Hong Kong, Hong Kong, Chen, Y. G., and Gu, S. J.. Bosonization study of quantum phase transitions in the one-dimensional asymmetric Hubbard model. United States: N. p., 2007. Web. doi:10.1103/PHYSREVB.75.165111.
Wang, Z. G., Department of Physics and the Institute of Theoretical Physics, Chinese University of Hong Kong, Hong Kong, Chen, Y. G., & Gu, S. J.. Bosonization study of quantum phase transitions in the one-dimensional asymmetric Hubbard model. United States. doi:10.1103/PHYSREVB.75.165111.
Wang, Z. G., Department of Physics and the Institute of Theoretical Physics, Chinese University of Hong Kong, Hong Kong, Chen, Y. G., and Gu, S. J.. Sun . "Bosonization study of quantum phase transitions in the one-dimensional asymmetric Hubbard model". United States. doi:10.1103/PHYSREVB.75.165111.
@article{osti_20957817,
title = {Bosonization study of quantum phase transitions in the one-dimensional asymmetric Hubbard model},
author = {Wang, Z. G. and Department of Physics and the Institute of Theoretical Physics, Chinese University of Hong Kong, Hong Kong and Chen, Y. G. and Gu, S. J.},
abstractNote = {The quantum phase transitions in the one-dimensional asymmetric Hubbard model are investigated with the bosonization approach. The conditions for the phase transition from density wave to phase separation, the correlation functions, and their exponents are obtained analytically. Our results show that the difference between the hopping integrals for up- and down-spin electrons is crucial for the occurrence of the phase separation. When the difference is large enough, the phase separation will appear even if the on-site interaction is small.},
doi = {10.1103/PHYSREVB.75.165111},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 16,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
  • We address some open questions regarding the phase diagram of the one-dimensional Hubbard model with asymmetric hopping coefficients and balanced species. In the attractive regime we present a numerical study of the passage from on-site pairing dominant correlations at small asymmetries to charge-density waves in the region with markedly different hopping coefficients. In the repulsive regime we exploit two analytical treatments in the strong- and weak-coupling regimes in order to locate the onset of phase separation at small and large asymmetries, respectively.
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