论文标题
基于Transmon的表面代码的泄漏检测
Leakage detection for a transmon-based surface code
论文作者
论文摘要
在许多领先的实验平台中存在的量子计算子空间之外的泄漏构成了量子误差校正（QEC）的威胁误差。我们通过隐藏的Markov模型（HMM）开发泄漏检测方案，以用于基于Transmon的表面代码实现。通过对距离3表面代码（Surface-17）进行逼真的密度 - 矩阵模拟，我们观察到泄漏被迅速投射，并导致相邻稳定器的表面代码缺陷概率增加。与Ancilla Qubits的模拟读数一起，这种增加可以准确检测泄漏的时间和位置。我们通过泄漏后泄漏，将大约47％的数据丢弃，将逻辑错误率恢复到内存分解点以下。通过HMMS泄漏检测为近期QEC示范，有针对性的泄漏减少和泄漏感知的解码打开了前景，并且适用于其他实验平台。
Leakage outside of the qubit computational subspace, present in many leading experimental platforms, constitutes a threatening error for quantum error correction (QEC) for qubits. We develop a leakage-detection scheme via Hidden Markov models (HMMs) for transmon-based implementations of the surface code. By performing realistic density-matrix simulations of the distance-3 surface code (Surface-17), we observe that leakage is sharply projected and leads to an increase in the surface-code defect probability of neighboring stabilizers. Together with the analog readout of the ancilla qubits, this increase enables the accurate detection of the time and location of leakage. We restore the logical error rate below the memory break-even point by post-selecting out leakage, discarding about 47% of the data. Leakage detection via HMMs opens the prospect for near-term QEC demonstrations, targeted leakage reduction and leakage-aware decoding and is applicable to other experimental platforms.
