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arXiv 1504.05971cond-mat.mes-hallcond-mat.dis-nncond-mat.quant-gascond-mat.str-el
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幂律跳跃链中的无序驱动跃迁

Disorder-driven transition in a chain with power-law hopping

M. Garttner, S. V. Syzranov, A. M. Rey, V. Gurarie, L. Radzihovsky

摘要:

我们研究了一个具有幂律准粒子色散$\propto |k|^α\sign k$的一维系统,在一个短程关联随机势的存在下,证明了对于$α<1/2$,它表现出一个无序驱动的量子相变,其临界性质类似于文献[1]中研究的高维半导体带边附近的局域化跃迁. 1和2.尽管在考虑的一维系统中没有局部化,但无序驱动的转变表现为例如无序平均态密度的临界形式。我们通过数值模拟证实了相变的存在,并发现临界指数和临界无序强度是$α$的函数。因此,建议的系统提供了一个方便的平台,最近预测的非常规高维局域化效应的数值研究,并有可能在实验实现的超冷原子链中的光阱。

英文摘要:

We study a 1D system with a power-law quasiparticle dispersion $\propto |k|^α\sign k$ in the presence of a short-range-correlated random potential and demonstrate that for $α<1/2$ it exhibits a disorder-driven quantum phase transition with the critical properties similar to those of the localisation transition near the edge of the band of a semiconductor in high dimensions, studied in Refs. 1 and 2. Despite the absence of localisation in the considered 1D system, the disorder-driven transition manifests itself, for example, in a critical form of the disorder-averaged density of states. We confirm the existence of the transition by numerical simulations and find the critical exponents and the critical disorder strength as a function of $α$. The proposed system thus presents a convenient platform for numerical studies of the recently predicted unconventional high-dimensional localisation effects and has the potential for experimental realisations in chains of ultracold atoms in optical traps.

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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