Detecting confined and deconfined spinons in dynamical quantum simulations
Detecting confined and deconfined spinons in dynamical quantum simulations
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DOI：
10.1103/physrevresearch.4.013193
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发表时间：
2021-10
影响因子：
4.2
通讯作者：
Qiao Li;J. Cui;Wei Li
中科院分区：
文献类型：
--
作者：
Qiao Li;J. Cui;Wei Li
动力学自旋结构因子（DSF）包含了相互作用量子自旋系统中集体激发的指纹信息。在固态实验中，可以通过中子散射测量DSF。然而，通过多体模拟精确地计算光谱特性通常是具有挑战性的。目前，量子模拟和计算是一个蓬勃发展的研究领域，被认为是一个非常有前途的平台，模拟量子多体系统。在这项工作中，我们建立了多体动力学和量子模拟之间的联系，通过研究直接产物态上测量的非平衡DSF（nDSF），这是在当代量子模拟器中可以使用的Rydberg原子，超导量子比特等。基于横场伊辛链的多体计算，我们发现nDSF可以灵敏地探测与双自旋产生和自旋-反自旋过程等有关的多自旋连续谱。此外，我们进一步证明了在有限的纵向场下，低能自旋子可以被限制--形成自旋束缚态。我们的结果为高纠缠量子多体系统分数激发的量子模拟和操纵铺平了道路。
Dynamical spin-structure factor (DSF) contains fingerprint information of collective excitations in interacting quantum spin systems. In solid state experiments, DSF can be measured through neutron scatterings. However, it is in general challenging to compute the spectral properties accurately via many-body simulations. Currently, quantum simulation and computation constitute a thriving research field, which are believed to provide a very promising platform for simulating quantum many-body systems. In this work, we establish a link between the many-body dynamics and quantum simulations by studying the non-equilibrium DSF (nDSF) measured on direct product states, which are accessible in contemporary quantum simulators with Rydberg atoms, superconducting qubits, etc. Based on the many-body calculations of transverse field Ising chains, we find the nDSF can be used to sensitively probe the multi-spinon continua associated with the two-spinon creation and the spinon-antispinon process, etc. Moreover, we further demonstrate that the low-energy spinons can be confined -- forming spinon bound states -- under a finite longitudinal field. Our results pave the way of quantum simulation and manipulation of fractional excitations in highly-entangled quantum many-body systems.