MISC

2018年8月10日

(De)localization of Fermions in Correlated-Spin Background

  • Tetsuya Takaishi
  • ,
  • Kazuhiko Sakakibara
  • ,
  • Ikuo Ichinose
  • ,
  • Tetsuo Matsui

記述言語
掲載種別
機関テクニカルレポート,技術報告書,プレプリント等

We study the (de)localization phenomena of one-component lattice fermions in<br />
spin backgrounds. The O(3) classical spin variables on sites fluctuate<br />
thermally through the ordinary nearest-neighbor coupling. Their complex<br />
two-component (CP$^1$-Schwinger boson) representation forms a composite U(1)<br />
gauge field on bond, which acts on fermions as a fluctuating hopping amplitude<br />
in a gauge invariant manner. For the case of antiferromagnetic (AF) spin<br />
coupling, the model has close relationship with the $t$-$J$ model of<br />
strongly-correlated electron systems. We measure the unfolded level spacing<br />
distribution of fermion energy eigenvalues and the participation ratio of<br />
energy eigenstates. The results for AF spin couplings suggest a possibility<br />
that, in two dimensions, all the energy eigenstates are localized. In three<br />
dimensions, we find that there exists a mobility edge, and estimate the<br />
critical temperature $T_{ß LD}(\delta)$ of the localization-delocalization<br />
transition at the fermion concentration $\delta$.

リンク情報
arXiv
http://arxiv.org/abs/arXiv:1808.03419
URL
http://arxiv.org/abs/1808.03419v2
ID情報
  • arXiv ID : arXiv:1808.03419

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