论文标题
部分可观测时空混沌系统的无模型预测
Purification-based quantum error mitigation of pair-correlated electron simulations
论文作者
论文摘要
量子计算平台开发的一个重要度量是模拟日益复杂的物理系统。在进行耐故障量子计算之前，必须采取强大的缓解误差策略来继续这种增长。在这里，我们研究了资历零电子配对子空间中的物理模拟，该子空间既为完全相关的模型提供了计算垫脚石，又提供了验证最近引入``基于纯化的'''错误缓解''误差策略的机会。我们将基于及时的量子资源（回声验证）或太空（虚拟蒸馏）的加倍量子资源（最多20美元的超导量子量子量子处理器）进行比较。我们观察到将误差降低了一到两个数量级以下，低于不太复杂的技术（例如，序列后）；由于系统尺寸而增加了误差减轻的增益。采用这些错误缓解策略可以实施迄今为止相关的化学系统最大的变异算法。从这些结果中推断性能使我们能够估计对电子结构进行超古典模拟的最低要求。我们发现，尽管基于纯化的错误误差获得了令人印象深刻的收益，但对于经典的差异化学模拟还是需要进行重大硬件改进。
An important measure of the development of quantum computing platforms has been the simulation of increasingly complex physical systems. Prior to fault-tolerant quantum computing, robust error mitigation strategies are necessary to continue this growth. Here, we study physical simulation within the seniority-zero electron pairing subspace, which affords both a computational stepping stone to a fully correlated model, and an opportunity to validate recently introduced ``purification-based'' error-mitigation strategies. We compare the performance of error mitigation based on doubling quantum resources in time (echo verification) or in space (virtual distillation), on up to $20$ qubits of a superconducting qubit quantum processor. We observe a reduction of error by one to two orders of magnitude below less sophisticated techniques (e.g. post-selection); the gain from error mitigation is seen to increase with the system size. Employing these error mitigation strategies enables the implementation of the largest variational algorithm for a correlated chemistry system to-date. Extrapolating performance from these results allows us to estimate minimum requirements for a beyond-classical simulation of electronic structure. We find that, despite the impressive gains from purification-based error mitigation, significant hardware improvements will be required for classically intractable variational chemistry simulations.
