Serbyn M, Knap M, Gopalakrishnan S, Papić Z, Yao N Y, Laumann C R, Abanin D A, Lukin M D, Demler E A
Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA and ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA.
Phys Rev Lett. 2014 Oct 3;113(14):147204. doi: 10.1103/PhysRevLett.113.147204.
We propose a method for detecting many-body localization (MBL) in disordered spin systems. The method involves pulsed coherent spin manipulations that probe the dephasing of a given spin due to its entanglement with a set of distant spins. It allows one to distinguish the MBL phase from a noninteracting localized phase and a delocalized phase. In particular, we show that for a properly chosen pulse sequence the MBL phase exhibits a characteristic power-law decay reflecting its slow growth of entanglement. We find that this power-law decay is robust with respect to thermal and disorder averaging, provide numerical simulations supporting our results, and discuss possible experimental realizations in solid-state and cold-atom systems.
我们提出了一种用于检测无序自旋系统中多体局域化（MBL）的方法。该方法涉及脉冲相干自旋操纵，通过这种操纵来探测给定自旋由于与一组远距离自旋的纠缠而产生的退相。它能让人区分MBL相、非相互作用局域相和退局域相。特别地，我们表明，对于适当选择的脉冲序列，MBL相呈现出特征性的幂律衰减，这反映了其纠缠的缓慢增长。我们发现这种幂律衰减在热平均和无序平均方面具有鲁棒性，提供了支持我们结果的数值模拟，并讨论了在固态和冷原子系统中可能的实验实现方式。
