论文标题
多体定位：自旋模型中的过渡
Many-Body Localization: Transitions in Spin Models
论文作者
论文摘要
我们研究自旋系统中的千古和多体局部阶段之间的过渡，这些阶段会受到淬灭疾病（包括海森贝格链和中央自旋模型）的样子。在这两种情况下，具有普通旋转长度$ 1/2 $和$ 1 $的系统通过精确的数值对角线化和随机矩阵技术进行了研究。 特别关注样本到样本差异$（Δ_SR）^2 $的连续差距比$ \ langle r \ rangle $用于不同的疾病实现。对于这两种类型的系统和旋转长度，我们在$Δ_SR$中发现最大值作为无序强度的函数，并伴随着$ \ langle r \ rangle $的拐点，这表明了从千古化到多体定位的过渡。发现关键障碍强度比最近文献中报道的值小一些。 有关过渡的更多信息可以从给定疾病实现内期望值的概率分布中获得。
We study the transitions between ergodic and many-body localized phases in spin systems, subject to quenched disorder, including the Heisenberg chain and the central spin model. In both cases systems with common spin lengths $1/2$ and $1$ are investigated via exact numerical diagonalization and random matrix techniques. Particular attention is paid to the sample-to-sample variance $(Δ_sr)^2$ of the averaged consecutive-gap ratio $\langle r\rangle$ for different disorder realizations. For both types of systems and spin lengths we find a maximum in $Δ_sr$ as a function of disorder strength, accompanied by an inflection point of $\langle r\rangle$, signaling the transition from ergodicity to many-body localization. The critical disorder strength is found to be somewhat smaller than the values reported in the recent literature. Further information about the transitions can be gained from the probability distribution of expectation values within a given disorder realization.
