论文标题
量子层造影的最佳和健壮的实验设计
Optimal and robust experiment design for quantum state tomography of star-topology register
论文作者
论文摘要
尽管量子状态断层扫描在量子系统的验证和基准测试中起着至关重要的作用，但如果限制了量子寄存器的可控性和测量，这是一项棘手的任务。在本文中，我们研究了星形学记录的量子状态层析成像，其中外围旋转的个体可寻址性是不可行的。基于恒星对称性，我们分解了希尔伯特空间，以减轻层析成像的复杂性并设计一种紧凑型策略，其测量数量最少。通过优化信息传输的参数化量子电路，还提高了针对测量误差的鲁棒性。此外，我们将此方法应用于10旋转星际学登记册，并证明了其表征大型系统的能力。我们的结果可以帮助未来对量子系统的调查，并具有量子控制和测量能力受限的量子系统。
While quantum state tomography plays a vital role in the verification and benchmarking of quantum systems, it is an intractable task if the controllability and measurement of quantum registers are constrained. In this paper, we study the quantum state tomography of star-topology registers, in which the individual addressability of peripheral spins is infeasible. Based on the star-symmetry, we decompose the Hilbert space to alleviate the complexity of tomography and design a compact strategy with minimum number of measurements. By optimizing the parameterized quantum circuit for information transfer, the robustness against measurement errors is also improved. Furthermore, we apply this method to a 10-spin star-topology register and demonstrate its ability to characterize large-scale systems. Our results can help future investigations of quantum systems with constrained ability of quantum control and measurement.
