论文标题
旨在模拟量子计算机上的晶格计理论中的2D效应
Towards simulating 2D effects in lattice gauge theories on a quantum computer
论文作者
论文摘要
规格理论是描述自然基本层面的最成功的理论,但是获得分析或数值解决方案通常仍然是一个挑战。我们提出了一种实验量子模拟方案,用于研究使用现有量子技术的二维量子电动力学(2D QED)中的基态特性。该提案建立在晶格量规理论的基础上,作为ARXIV:2006.14160中的有效自旋模型,该模型减少了消除冗余自由度和使用有效的截断方案来减少所需的量子数。后者赋予我们的提议,以达到控制良好的连续体限制。我们的协议原则上可以扩展到大晶格,并提供将晶格模拟连接到低能可观察数量的透视图,例如在连续理论中,强子频谱。通过包括动态物质和非最低规格场截断,我们提供了新的机会,可以观察到对当今量子硬件的2D影响。更具体地说,我们提出了两个基于磁场效应研究的基于差异量子量化的协议,并迈出了重要的第一步,以计算QED的运行耦合。对于这两种情况,我们都包括基于量子的硬件的变分量子电路,我们明确地将其应用于被困的离子量子计算机。我们经典地模拟了所提出的VQE实验,以计算现实条件下所需的测量预算。尽管对被困离子进行了可行性分析,但我们的方法可以很容易地适应其他平台。这里提出的技术,再加上量子硬件的进步铺平了铺平的道路,从而通过扩展我们的框架以包括费米子电位或拓扑术语来超越经典模拟的能力。
Gauge theories are the most successful theories for describing nature at its fundamental level, but obtaining analytical or numerical solutions often remains a challenge. We propose an experimental quantum simulation scheme to study ground state properties in two-dimensional quantum electrodynamics (2D QED) using existing quantum technology. The proposal builds on a formulation of lattice gauge theories as effective spin models in arXiv:2006.14160, which reduces the number of qubits needed by eliminating redundant degrees of freedom and by using an efficient truncation scheme for the gauge fields. The latter endows our proposal with the perspective to take a well-controlled continuum limit. Our protocols allow in principle scaling up to large lattices and offer the perspective to connect the lattice simulation to low energy observable quantities, e.g. the hadron spectrum, in the continuum theory. By including both dynamical matter and a non-minimal gauge field truncation, we provide the novel opportunity to observe 2D effects on present-day quantum hardware. More specifically, we present two Variational Quantum Eigensolver (VQE) based protocols for the study of magnetic field effects, and for taking an important first step towards computing the running coupling of QED. For both instances, we include variational quantum circuits for qubit-based hardware, which we explicitly apply to trapped ion quantum computers. We simulate the proposed VQE experiments classically to calculate the required measurement budget under realistic conditions. While this feasibility analysis is done for trapped ions, our approach can be easily adapted to other platforms. The techniques presented here, combined with advancements in quantum hardware pave the way for reaching beyond the capabilities of classical simulations by extending our framework to include fermionic potentials or topological terms.