Prescription for experimental determination of the dynamics of a quantum black box

Equivalence determination of unitary operations

We study equivalence determination of unitary operations, a task analogous to quantum state discrimination. The candidate states are replaced by unitary operations given as a quantum sample, i.e., a black-box device implementing a candidate unitary operation, and the discrimination target becomes another black-box. The task is an instance of higher-order quantum computation with the black-boxes as input. The optimal error probability is calculated by semidefinite programs. Arbitrary quantum operations applied between the black-boxes in a general protocol provide advantages over protocols restr…

实用的黑盒哈密顿量学习

Practical Black Box Hamiltonian Learning

针对系统访问受限下的量子多体哈密顿量参数学习问题，提出基于导数估计的改进协议，降低了结构参数标度依赖并给出超参数最优数值界限，在80量子比特系统上验证了其大规模实用性。