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Hidden XY structure of the bond-charge Hubbard model

192   0   0.0 ( 0 )
 نشر من قبل Marco Roncaglia
 تاريخ النشر 2010
  مجال البحث فيزياء
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The repulsive one-dimensional Hubbard model with bond-charge interaction (HBC) in the superconducting regime is mapped onto the spin-1/2 XY model with transverse field. We calculate correlations and phase boundaries, realizing an excellent agreement with numerical results. The critical line for the superconducting transition is shown to coincide with the analytical factorization line identifying the commensurate-incommensurate transition in the XY model.



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