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Low-energy spectra in the t-J type models at light doping

Wei-Cheng Lee·T. K. Lee·Chang-Ming Ho·P. W. Leung
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Abstract

Based on a variational approach, we propose that there are two kinds of low energy states in the t-J type models at low doping. In a quasi-particle state an unpaired spin bound to a hole with a well-defined momentum can be excited with spin waves. The resulting state shows a suppression of antiferromagnetic order around the hole with the profile of a {\em spin bag}. These spin-bag states with spin and charge or hole separated form a continuum of low-energy excitations. Very different properties predicted by these two kinds of states explain a number of anomalous results observed in the exact diagonalization studies on small clusters up to 32 sites.

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Wei-Cheng Lee, T. K. Lee, Chang-Ming Ho, P. W. Leung. 2003-06-17. Low-energy spectra in the t-J type models at light doping. https://doi.org/10.1103/physrevlett.91.057001

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