Title: Optimally robust shortcuts to population inversion in cat-state qubits Show Chinese title

Title: 最优鲁棒捷径实现猫态量子比特的反转

Abstract: Cat-state qubits formed by photonic coherent states are a promising candidate for realizing fault-tolerant quantum computing. Such logic qubits have a biased noise channel that the bit-flip error dominates over all the other errors. In this manuscript, we propose an optimally robust protocol using the control method of shortcuts to adiabaticity to realize a nearly perfect population inversion in a cat-state qubit. We construct a shortcut based on the Lewis-Riesenfeld invariant and examine the stability versus different types of perturbations for the fast and robust population inversion. Numerical simulations demonstrate that the population inversion can be mostly insensitive to systematic errors in our protocol. Even when the parameter imperfection rate for bit-flip control is $20\%$, the final population of the target state can still reach $\geq 99\%$. The optimally robust control provides a feasible method for fault-tolerant and scalable quantum computation. Show Chinese abstract

Abstract: 由光相干态形成的猫态量子比特是实现容错量子计算的一个有前景的候选者。 这种逻辑量子比特具有一个偏向噪声通道，其中比特翻转错误主导所有其他错误。 在本文中，我们提出了一种最优鲁棒协议，使用绝热捷径控制方法来实现在猫态量子比特中的近似完全布居反转。 我们基于刘易斯-赖斯恩费尔德不变量构建了一个捷径，并研究了快速且稳健的布居反转对于不同类型的扰动的稳定性。 数值模拟表明，在我们的协议中，布居反转对系统误差大多不敏感。 即使比特翻转控制的参数不完美率为$20\%$，目标状态的最终布居仍可达到$\geq 99\%$。 最优鲁棒控制为容错和可扩展的量子计算提供了一种可行的方法。