使用单个旁观者量子比特减轻多级随机电报噪声
Multi-level Random-Telegraph Noise Mitigation using a Single Spectator Qubit
AI总结：
针对量子技术中环境噪声影响量子相干的问题，开发基于单个旁观者量子比特的方法减轻多级随机电报噪声。通过推导相干动力学、开发减轻方案及提出自适应协议，经数值模拟验证该策略能有效抑制退相干，性能与两态情况相当。
AI中文摘要：
在环境噪声存在的情况下保持量子相干是量子技术的主要挑战之一。使用旁观者量子比特（SQ）减轻噪声最近成为一种有前途的方法，能够在不干扰数据量子比特（DQ）的情况下间接探测噪声。然而，现有的关于最终性能的分析仅限于两态随机电报过程噪声，无法捕捉环境中可能出现的更复杂的噪声过程。因此，我们开发了一种基于SQ的噪声减轻方法，用于处理受到一般多级波动噪声影响的DQ。我们首先推导了在这种噪声下DQ的相干动力学，然后开发了一种减轻方案，通过连续的SQ测量推断噪声信息并用于相位校正。提出了一种内存高效的启发式自适应协议，根据当前噪声估计动态选择SQ测量时间和角度。数值模拟表明，所提出的策略在多级噪声下显著抑制了退相干，尽管噪声过程更加复杂，但性能与两态情况相当。
英文摘要：
Preserving quantum coherence in the presence of environmental noise is one of the principal challenges for quantum technologies. Noise mitigation using spectator qubits (SQs) has recently emerged as a promising approach, enabling indirect probing of the noise without disturbing the data qubit (DQ). However, existing analyses that probe ultimate performance have been restricted to two-state random telegraph process noise, which does not capture more complex noise processes that may arise in the environment. Therefore, we here develop a SQ-based noise mitigation for DQs subject to general multi-level fluctuator noise. We first derive the coherence dynamics of the DQ under such noise, then develop a mitigation scheme in which information about the noise is inferred from sequential SQ measurements and used for phase correction. A memory-efficient heuristic adaptive protocol is proposed to dynamically select the SQ measurement time and angle based on the current noise estimate. Numerical simulations demonstrate that the proposed strategy significantly suppresses decoherence under multi-level noise, achieving performance comparable to that in the two-level case despite the increased complexity of the noise process.
