论文标题
电阻率及其在无序多体系统中的波动：从链到平面
Resistivity and its fluctuations in disordered many-body systems: from chains to planes
论文作者
论文摘要
我们研究了一个量子粒子，该量子与硬核玻色子结合并在带有$ r $ the的无序梯子上传播。在安德森州之间的玻色子辅助转变的速率方程的帮助下，研究了粒子动力学。我们证明，对于有限的$ r <\ infty $和足够强大的疾病，动态是延伸的，而$ r \ to \ infty $的二维平面系统似乎对于任意强烈的疾病而言是扩散的。可以通过电阻率的统计波动来识别从扩散到延伸方案的过渡。扩散状态中的相应分配功能具有脂肪尾巴，随着系统尺寸$ l $缩小速度较慢，速度慢于$ 1/\ sqrt {l} $。最后，我们提供的证据表明，在多体定位的标准模型，即在强烈的量子旋转链中，同样的非高斯波动也会出现。
We study a quantum particle coupled to hard-core bosons and propagating on disordered ladders with $R$ legs. The particle dynamics is studied with the help of rate equations for the boson-assisted transitions between the Anderson states. We demonstrate that for finite $R < \infty$ and sufficiently strong disorder the dynamics is subdiffusive, while the two-dimensional planar systems with $R\to \infty$ appear to be diffusive for arbitrarily strong disorder. The transition from diffusive to subdiffusive regimes may be identified via statistical fluctuations of resistivity. The corresponding distribution function in the diffusive regime has fat tails which decrease with the system size $L$ much slower than $1/\sqrt{L}$. Finally, we present evidence that similar non--Gaussian fluctuations arise also in standard models of many-body localization, i.e., in strongly disordered quantum spin chains.
