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arXiv · 1011.0255

Bound state of a hole and a triplet spin in the $t_1$-$t_2$-$J_1$-$J_2$ model

Kazuhiro Sano·Ken'ichi Takano
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Abstract

We show that a hole and a triplet spin form a bound state in a nearly half-filled band of the one- and two-dimensional $t_1$-$t_2$-$J_1$-$J_2$ models. Numerical calculation indicates that the bound state is a spatially small object and moves as a composite particle with spin 1 and charge $+e$ in the spin-gapped background. Two bound states repulsively interact with each other in a short distance and move independently as long as they keep their distance. If a finite density of bound states behave as bosons, the system undergoes the Bose-Einstein condensation which means a superconductivity with charge $+e$.

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Kazuhiro Sano, Ken'ichi Takano. 2010-11-01. Bound state of a hole and a triplet spin in the $t_1$-$t_2$-$J_1$-$J_2$ model. https://doi.org/10.1103/physrevb.83.054421

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