发表机构
Faculty of Engineering, University of Yamanashi（山梨大学工学部）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出一种后处理重构方法，利用纯辅助量子比特模拟有限温度开放系统动力学，避免热态制备开销，适用于$U(1)$对称碰撞模型，可重用数据于不同温度。
AI 中文摘要
在基于门控的量子计算机上模拟开放系统动力学，为通过可编程量子处理探索耗散量子现象提供了一条途径。碰撞模型通过顺序的系统-辅助量子比特碰撞来表示环境，提供了一种直接且灵活的框架。然而，在有限温度下，它们通常需要重复制备热辅助量子比特，增加了电路开销和门误差。在这里，我们表明，对于一大类具有$U(1)$对称性的系统-辅助量子比特相互作用，有限温度动力学可以从使用正交基态中的纯辅助量子比特的模拟中重构出来。目标温度仅通过经典后处理所得纯分支数据进入，允许相同数据在不同温度下重用，无需额外的量子处理。绕过显式热态制备减少了辅助量子比特制备开销和制备引起的误差。
英文摘要
Simulating open-system dynamics on gate-based quantum computers offers a route to exploring dissipative quantum phenomena through programmable quantum processing. Collision models provide a direct and flexible framework by representing the environment through sequential system--ancilla collisions. At finite temperatures, however, they typically require repeated preparation of thermal ancillas, adding circuit overhead and gate errors. Here, we show that, for a broad class of $U(1)$-symmetric system--ancilla interactions, finite-temperature dynamics can instead be reconstructed from simulations with pure ancillas in orthogonal basis states. The target temperature enters only through classical post-processing of the resulting pure-branch data, allowing the same data to be reused for different temperatures without additional quantum processing. Bypassing explicit thermal-state preparation reduces ancilla-preparation overhead and preparation-induced errors.
