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arXiv · 1510.06881

Ferromagnetic clouds caused by hole motion in a one-dimensional $t$-$J$ mode

Kazuhiro Sano·Ken'ichi Takano
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Abstract

The one-dimensional $t_1$-$t_2$-$J_1$-$J_2$ model is examined in the one-hole case, in which the total number of electrons is one less than the number of the lattice sites. The ground-state phase diagram includes a series of partial ferromagnetic phases, which are stacked in a regime of positive and small $J_1$. We find that the ground state in each of these partial ferromagnetic phases includes a ferromagnetic cloud, which is a multiple-spin bound state together with the hole. The ferromagnetic cloud is a large magnetic polaron with a heavy mass in a single-band electronic system and is supposedly formed as a result of Nagaoka ferromagnetism which locally works around the hole.

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Kazuhiro Sano, Ken'ichi Takano. 2015-10-23. Ferromagnetic clouds caused by hole motion in a one-dimensional $t$-$J$ mode. https://doi.org/10.7566/jpsj.85.094714

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