多体相互作用连接的有限无序网络中的量子效率

Connecting Topological Anderson and Mott Insulators in Disordered Interacting Fermionic Systems

The topological Anderson and Mott insulators are two phases that have so far been separately and widely explored beyond topological band insulators. Here we combine the two seemingly different topological phases into a system of spin-1/2 interacting fermionic atoms in a disordered optical lattice. We find that the topological Anderson and Mott insulators in the noninteracting and clean limits can be adiabatically connected without gap closing in the phase diagram of our model. Lying between the two phases, we uncover a disordered correlated topological insulator, which is induced from a trivia…

Dynamics of decoherence of an entangled pair of qubits locally connected to a one-dimensional disordered spin chain

We study the non-equilibrium evolution of concurrence of a Bell pair constituted of two qubits, through the measurement of Loschmidt echo (LE) under the scope of generalized central spin model. Having detected the Griffiths phase via derivative of LE in equilibrium, we show that in the non-equilibrium situation, the spin chain requires a temporal window to realize the effect of disorder. We show that within this timescale, LE falls off exponentially and this decay is maximally controlled by the initial states and coupling strength. Our detail investigation suggests that there actually exist th…

具有长程交换相互作用的无序自旋链中的激发转移

Excitation transfer in disordered spin chains with long-range exchange interactions

本文研究含对角与非对角无序的长程相互作用自旋链中的激发转移，通过分析单激发本征态局域化长度筛选边界通道，并比较弱静态耦合与含时受激绝热通道方案，证明后者性能更优。

无序相互作用多体网络中的有效量子输运

Efficient quantum transport in disordered interacting many-body networks

研究了$n$费米子在由$k$ -体相互作用连接的$l$单粒子态无序网络中的相干输运。这些网络模型的嵌入式高斯随机矩阵集成（EGE）。当系统中充满$n \sim l-1$和$k\sim n/2$时，电导带宽和系综平均总电流达到最大值。对于情况$k=1$和$k=n$，带宽最小。我们发现，对于所有参数的运输显着增强时，中心对称系综（csEGE）被认为是。在这种情况下，传输显示出许多完美传输的共振。通过谱分解分析透射率，我们发现中心对称性导致了强相关性，增强了分布的极值。这抑制了系统中的相消干涉效应，并因此引起增强整体传输的无反向散射的传输谐振。对于$n=l-1$，csEGE的总电流分布具有非常大的主峰，接近观察到的最高电流。

Emergent statistical mechanics from properties of disordered random matrix product states

The study of generic properties of quantum states has led to an abundance of insightful results. A meaningful set of states that can be efficiently prepared in experiments are ground states of gapped local Hamiltonians, which are well approximated by matrix product states. In this work, we introduce a picture of generic states within the trivial phase of matter with respect to their non-equilibrium and entropic properties: We do so by rigorously exploring non-translation-invariant matrix product states drawn from a local i.i.d. Haar-measure. We arrive at these results by exploiting techniques …

平均-精确混合反常与相容相

Average-exact mixed anomalies and compatible phases

本文研究同时具有平均对称性和精确对称性的无序系统，论证了平均-精确混合反常禁止无特征混合态，并发现了无清洁极限对应物的新无序相，包括强到弱对称性破缺玻璃态和平均拓扑序，通过可解晶格模型和场论判据加以论证。

Stability of dynamical quantum phase transitions in quenched topological insulators: From multiband to disordered systems

Dynamical quantum phase transitions (DQPTs) represent a counterpart in non-equilibrium quantum time evolution of thermal phase transitions at equilibrium, where real time becomes analogous to a control parameter such as temperature. In quenched quantum systems, recently the occurrence of DQPTs has been demonstrated, both with theory and experiment, to be intimately connected to changes of topological properties. Here, we contribute to broadening the systematic understanding of this relation between topology and DQPTs to multi-orbital and disordered systems. Specifically, we provide a detailed …

A Self-Consistent Quantum Field Theory for Random Lasing

The spatial formation of coherent random laser modes in strongly scattering disordered random media is a central feature in the understanding of the physics of random lasers. We derive a quantum field theoretical method for random lasing in disordered samples of complex amplifying Mie resonators which is able to provide self-consistently and free of any fit parameter the full set of transport characteristics at and above the laser phase transition. The coherence length and the correlation volume respectively is derived as an experimentally measurable scale of the phase transition at the laser …

全连通Ising铁磁体量子退火和模拟退火的直接比较

Direct comparison of quantum and simulated annealing on a fully-connected Ising ferromagnet

我们比较量子退火（QA，通过薛定谔动力学）和模拟退火（SA，通过一个经典的主方程）的性能在$p$自旋无限程铁磁伊辛模型，通过缓慢驱动系统跨越其平衡，量子或经典，相变。当相变是二阶（$p=2$，熟悉的双自旋伊辛相互作用）时，SA显示出比QA显著的指数加速。对于一阶相变（$p \ge 3$，即，与多自旋伊辛相互作用）相比，经典的退火动力学似乎仍然停留在无序相，而我们有明确的证据表明，QA显示出当总退火时间$τ$增加时，尽管以相当慢的（对数）方式，但朝向$0$减小的残余能量。这是一个罕见的例子，其中有限的量子加速，加速QA超过SA，已被证明存在的直接解决方案的薛定谔和主方程结合非平衡朗道-齐纳分析。我们还分析了该模型的时间QA动力学，发现一个$1/τ^2$行为的所有有限值的$p$，所预测的绝热定理的量子力学。讨论了Grover搜索极限$p({\rm odd})=\infty$。