近日，西班牙圣地亚哥德孔波斯特拉大学的Wenyang Qian及其研究团队取得一项新进展。经过不懈努力，他们实现费米子热场理论中的量子计算。相关研究成果已于2024年7月18日在国际知名学术期刊《高能物理杂志》上发表。

在这项工作中，研究人员使用量子算法研究了只涉及费米子的热场理论。研究人员首先通过数字量子计算机上的量子比特深入研究费米子场的表现，以及用于评估通用量子场论热性质的量子算法，如量子虚时间演化。具体而言，研究人员使用量子模拟器展示了1+1维马约拉纳费米子的热场理论的热分布和能量密度等数值结果。除了自由场理论，研究人员还研究了与空间均匀的马约拉纳场耦合所产生的相互作用的影响。

在这两种情况下，研究人员通过解析分析明确指出，系统的热性质可以用相空间分布来描述，量子模拟结果符合解析和半经典的期望。这项研究工作是了解热不动点的重要一步，为实时热化的量子模拟做准备。

据悉，有限温度下量子场的热性质对于理解强相互作用物质至关重要，量子计算的最新发展为研究提供了另一种有前途的途径。

附：英文原文

Title: Quantum computation in fermionic thermal field theories

Author: Qian, Wenyang, Wu, Bin

Issue&Volume: 2024-07-18

Abstract: Thermal properties of quantum fields at finite temperature are crucial to understanding strongly interacting matter and recent development in quantum computing has provided an alternative and promising avenue of study. In this work, we study thermal field theories involving only fermions using quantum algorithms. We first delve into the presentations of fermion fields via qubits on digital quantum computers alongside the quantum algorithms such as quantum imaginary time evolutions employed to evaluate thermal properties of generic quantum field theories. Specifically, we show numerical results such as the thermal distribution and the energy density of thermal field theories for Majorana fermions in 1+1 dimensions using quantum simulators. In addition to free field theory, we also study the effects of interactions resulting from coupling with a spatially homogeneous Majorana field. In both cases, we show analytically that thermal properties of the system can be described using phase-space distributions, and the quantum simulation results agree with analytical and semiclassical expectations. Our work is an important step to understand thermal fixed points, preparing for quantum simulation of thermalization in real time.

DOI: 10.1007/JHEP07(2024)166

Source: https://link.springer.com/article/10.1007/JHEP07(2024)166