arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1503.08128cond-mat.mes-hallcond-mat.dis-nn
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强定域相互作用系统的格林函数

Green functions of interacting systems in the strongly localized regime

A. N. Somoza, M. Ortuño, V. Gasparian, M. Pino

摘要:

本文发展了一种计算零温强定域极限下一维多体系统单粒子格林函数的方法。我们的方法,定位器扩展的基础上,总结了配置空间中所有可能的前向散射路径的贡献。我们证明了费米子的格林函数因式分解时,系统可以分裂成两个非相互作用的区域。这意味着,对于最近邻相互作用,格林函数在连接具有相同占用的两个站点的每个链接处进行因子分解。因此,我们表明,相互作用系统的电导分布函数是对数正态分布,在相同的普适性类为非相互作用系统。我们已经开发了一个数值程序来计算的基态和格林函数,生成所有可能的路径中的配置空间。我们比较本地化长度计算与我们的程序通过精确对角化得到的。随着无序度的增加,后者平滑地收敛到我们的结果。

英文摘要:

We have developed an approach to calculate the single-particle Green function of a one-dimensional many-body system in the strongly localized limit at zero temperature. Our approach, based on the locator expansion, sums the contributions of all possible forward scattering paths in configuration space. We demonstrate for fermions that the Green function factorizes when the system can be splited into two non interacting regions. This implies that for nearest neighbors interactions the Green function factorizes at every link connecting two sites with the same occupation. As a consequence we show that the conductance distribution function for interacting systems is log-normal, in the same universality class as for non-interacting systems. We have developed a numerical procedure to calculate the ground state and the Green function, generating all possible paths in configuration space. We compare the localization length computed with our procedure with the one obtained via exact diagonalization. The latter smoothly converges to our results as the disorder increases.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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