arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2008.08980quant-phcond-mat.str-elhep-lathep-ph
收藏

格点规范理论与噪声中尺度量子器件的动力学量子相变

Lattice gauge theory and dynamical quantum phase transitions using noisy intermediate scale quantum devices

Simon Panyella Pedersen, Nikolaj Thomas Zinner

摘要:

格点规范理论是一个迷人的和丰富的一类理论有关的粒子物理学的最基本的模型,随着实验控制的量子水平的增加,有一个非平衡效应,如动态量子相变的兴趣越来越大。为了证明这些物理理论如何在近期量子器件中得到应用,我们研究了(1+1)D U(1)量子链模型在质量项猝灭后的动力学行为。我们发现,该系统经历动态量子相变的所有系统尺寸考虑,即使是最小的动态可以解析求解。我们设计了一个规范不变的弦序参量,它的零点与Loschlord振幅的结构相关,使得序参量可用于近期器件的实验研究。Loscherton振幅的零点以及我们的序参量的零点由其相位中的涡旋揭示,其可以由拓扑不变的缠绕数计数。考虑到有噪声的中尺度量子器件,我们提出了一类超导电路,用于U(1)量子链路模型的一般实现。这些电路的原理可以推广到实现其他更复杂的规范对称性。此外,该电路可以模块化地缩放到任何晶格配置。仿真电路动态与现实的电路参数,我们发现,它实现了稳定的平均保真度为$ 99.5\% $或更高的目标动态。最后,我们考虑读出的电路使用的方法,产生的所有自由度的信息与谐振器色散耦合到其中的一个子集。这构成了一个直接和相对简单的协议,以访问洛施图振幅和序参量。

英文摘要:

Lattice gauge theories are a fascinating and rich class of theories relating to the most fundamental models of particle physics, and as experimental control on the quantum level increases there is a growing interest in non-equilibrium effects such as dynamical quantum phase transitions. To demonstrate how these physical theories can be accessed in near-term quantum devices, we study the dynamics of a (1+1)D U(1) quantum link model following quenches of its mass-term. We find that the system undergoes dynamical quantum phase transitions for all system sizes considered, even the smallest where the dynamics can be solved analytically. We devise a gauge invariant string order parameter whose zeros correlates with the structure of the Loschmidt amplitude, making the order parameter useful for experimental study in near-term devices. The zeros of the Loschmidt amplitude as well as the zeros of our order parameter are revealed by vortices in their phases, which can be counted by a topologically invariant winding number. With noisy intermediate scale quantum devices in mind, we propose a class of superconducting circuits for the general implementation of U(1) quantum link models. The principles of these circuits can be generalized to implement other, more complicated gauge symmetries. Furthermore, the circuit can be modularly scaled to any lattice configuration. Simulating the circuit dynamics with realistic circuit parameters we find that it implements the target dynamics with a steady average fidelity of $ 99.5\% $ or higher. Finally, we consider readout of the circuit using a method that yields information about all the degrees of freedom with resonators coupled dispersively to only a subset of them. This constitutes a direct and relatively straightforward protocol to access both Loschmidt amplitudes and the order parameter.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑