论文标题
通过取消边界取消误抑制量子退火的演示
Demonstration of error-suppressed quantum annealing via boundary cancellation
论文作者
论文摘要
开放系统的边界取消定理扩展了标准的量子绝热定理：假设liouvillian的间隙不会消失，这是由一个取消绝热协议的边界制备的状态与制剂末期消失时间衍生物数量缩小的稳定状态之间的距离。在这里，我们概括了边界取消定理，以便它也适用于liouvillian间隙消失的情况，并考虑进化的动态冻结的效果。我们使用量子退火硬件在实验中测试边界取消定理的预测，并找到与预测的误差抑制的定性一致性，尽管使用了仅近似所需的平滑计划的退火时间表。通过使用量子退火校正，进一步提高了性能，我们证明，与采用暂停以增强寻找基态的概率的方案相比，边界取消方案对参数变化的稳健性更大。
The boundary cancellation theorem for open systems extends the standard quantum adiabatic theorem: assuming the gap of the Liouvillian does not vanish, the distance between a state prepared by a boundary cancelling adiabatic protocol and the steady state of the system shrinks as a power of the number of vanishing time derivatives of the Hamiltonian at the end of the preparation. Here we generalize the boundary cancellation theorem so that it applies also to the case where the Liouvillian gap vanishes, and consider the effect of dynamical freezing of the evolution. We experimentally test the predictions of the boundary cancellation theorem using quantum annealing hardware, and find qualitative agreement with the predicted error suppression despite using annealing schedules that only approximate the required smooth schedules. Performance is further improved by using quantum annealing correction, and we demonstrate that the boundary cancellation protocol is significantly more robust to parameter variations than protocols which employ pausing to enhance the probability of finding the ground state.
