Department of Applied Physics, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
Optical Quantum Computing Research Team, RIKEN Center for Quantum Computing, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
Nat Commun. 2023 Jul 12;14(1):3817. doi: 10.1038/s41467-023-39195-w.
Measurement-based quantum computation with optical time-domain multiplexing is a promising method to realize a quantum computer from the viewpoint of scalability. Fault tolerance and universality are also realizable by preparing appropriate resource quantum states and electro-optical feedforward that is altered based on measurement results. While linear feedforward has been realized and become a common experimental technique, nonlinear feedforward was unrealized until now. In this paper, we demonstrate that a fast and flexible nonlinear feedforward realizes the essential measurement required for fault-tolerant and universal quantum computation. Using non-Gaussian ancillary states, we observed 10% reduction of the measurement excess noise relative to classical vacuum ancilla.
基于光学时域复用的基于测量的量子计算是一种很有前途的方法，可以从可扩展性的角度实现量子计算机。通过准备适当的资源量子态和基于测量结果进行修改的电光前馈，也可以实现容错和通用性。虽然已经实现了线性前馈，并成为一种常见的实验技术，但直到现在还没有实现非线性前馈。在本文中，我们证明了快速灵活的非线性前馈实现了容错和通用量子计算所需的基本测量。使用非高斯辅助态，我们观察到相对于经典真空辅助态，测量过剩噪声降低了 10%。
