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Two-Hole and Four-Hole Bound States in a t-J Ladder at half-filling

W. Zheng·C. J. Hamer
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Abstract

The two-hole excitation spectrum of the t-J ladder at half-filling is studied using linked-cluster series expansion methods. A rich spectrum of bound states emerges, particularly at small $t/J$. Their dispersion relations and coherence lengths are computed, along with the threshold behaviour as the bound states merge into the continuum. A class of 4-hole bound states is also studied, leading to the conclusion that phase separation occurs for $t/J \lesssim 0.5$, in agreement with other studies.

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W. Zheng, C. J. Hamer. 2002-04-24. Two-Hole and Four-Hole Bound States in a t-J Ladder at half-filling. https://doi.org/10.1103/physrevb.66.085112

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