论文标题
耦合量子点中Majorana模式的融合协议
Fusion protocol for Majorana modes in coupled quantum dots
论文作者
论文摘要
在最近的突破性实验[自然（伦敦）614，445（2023）]中，在隧道光谱中观察到了Majorana零模式的特征，这是由耦合量子点构建的最小Kitaev链。但是，作为伊斯林，Majoranas的非亚伯统计中最基本的财产尚待检测到。此外，最小的基塔夫链在质量上与拓扑超导体不同，因为它仅在最佳位置支持majora。因此，是否可以在此平台中以合理的鲁棒性来证明诸如编织和融合之类的非亚伯式特征并不明显。在这项工作中，我们从理论上提出了一种协议，用于检测由四个量子点组成的人工基塔伊夫链中的主要融合规则。与先前关于半导体 - 渗透纳米纳线平台的建议相反，在这里，我们不依赖于量子点链中难以实施的中镜超导岛。为了显示融合协议的鲁棒性，我们讨论了三种现实缺陷对融合结果的影响，例如糖尿病误差，dephasing错误和校准误差。我们还提出了使用量子电容的费米昂奇偶校验读数方案。我们的工作将阐明未来的实验，以检测量子点链中Majorana模式的非亚洲特性。
In a recent breakthrough experiment [Nature (London) 614, 445 (2023)], signatures of Majorana zero modes have been observed in tunnel spectroscopy for a minimal Kitaev chain constructed from coupled quantum dots. However, as Ising anyons, Majoranas' most fundamental property of non-Abelian statistics is yet to be detected. Moreover, the minimal Kitaev chain is qualitatively different from topological superconductors in that it supports Majoranas only at a sweet spot. Therefore, it is not obvious whether non-Abelian characteristics such as braiding and fusion can be demonstrated in this platform with a reasonable level of robustness. In this work, we theoretically propose a protocol for detecting the Majorana fusion rules in an artificial Kitaev chain consisting of four quantum dots. In contrast with the previous proposals for semiconductor-superconductor hybrid nanowire platforms, here we do not rely on mesoscopic superconducting islands, which are difficult to implement in quantum dot chains. To show the robustness of the fusion protocol, we discuss the effects of three types of realistic imperfections on the fusion outcomes, e.g., diabatic errors, dephasing errors, and calibration errors. We also propose a fermion parity readout scheme using quantum capacitance. Our work will shed light on future experiments on detecting the non-Abelian properties of Majorana modes in a quantum dot chain.
