环境记录从热退相干中解锁通用量子计算
Environmental records unlock universal quantum computation from thermal decoherence
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中文总结 AI 辅助
该研究精确分类了热退相干下稳定子处理器的计算能力，发现环境记录的选择决定其可经典模拟或量子通用，并给出边界条件与资源方案。
中文摘要 AI 辅助
在固定的热暴露下，相同的稳定子处理器可以是经典可模拟的，也可以是量子通用的，这取决于其控制器保留哪些环境记录。我们给出了在具有理想稳定子控制和独立局部马尔可夫浴的量子处理器中，能量计数热空闲仪器的精确计算分类。弛豫时间$T_1$、均匀相干时间$T_2$和平衡激发态布居$p_e$在$(1-p_e)T_2/T_1=1$处确定了一个精确的计算边界。如果每个位置都位于该边界或以下，则分支非负稳定子分解为自适应电路及其完整时间分辨交换记录提供了显式的高效经典采样器。在单个可重复访问的位置高于该边界时，适当的空闲持续时间和无交换条件提供了可蒸馏的辅助量子比特，并以多项式开销实现通用量子计算。在资源侧的有限温度下，在足够长且未分割的暴露下擦除记录会使平均通道成为稳定子测量-制备，即使是终端奇偶校验也只会产生可模拟的分支。然而，在同一暴露下，仅保留记录是否发生任何交换的比特仍然预示可蒸馏的辅助量子比特，因为热往返在其第一次交换已经移除相干性后恢复了奇偶性。
英文摘要
At a fixed thermal exposure, the same stabilizer processor can be classically simulable or quantum universal, depending on which environmental records its controller retains. We give an exact computational classification of energy-counting thermal-idle instruments in a quantum processor with ideal stabilizer control and independent local Markov baths. The relaxation time $T_1$, homogeneous coherence time $T_2$, and equilibrium excited-state population $p_e$ determine an exact computational boundary at $(1-p_e)T_2/T_1=1$. If every location lies at or below it, branchwise nonnegative stabilizer decompositions give an explicit efficient classical sampler for the adaptive circuit and its full time-resolved exchange record. Above it at a single repeatedly accessible location, a suitable idle duration and no-exchange conditioning supply distillable ancillas and enable universal quantum computation with polynomial overhead. At finite temperature on the resource side, erasing the record at a sufficiently long, unsplit exposure makes the averaged channel stabilizer measure-and-prepare, and even a terminal parity check then yields only simulable branches. Yet at that same exposure, retaining only the bit recording whether any exchange occurred still heralds distillable ancillas, because a thermal round trip restores the parity after its first exchange has already removed the coherence.
发表机构
- HK Institute of Quantum Science & Technology, The University of Hong Kong（香港量子科学研究所，香港大学）
- QICI Quantum Information and Computation Initiative, School of Computing and Data Science, The University of Hong Kong（QICI量子信息与计算倡议，计算与数据科学学院，香港大学）
机构由 AI 辅助整理，请以论文原文为准。
