Park Sunghun, Sim H-S, Recher Patrik
Departamento de Física Teórica de la Materia Condensada, Condensed Matter Physics Center (IFIMAC) and Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, 28049 Madrid, Spain.
Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 34141, Korea.
Phys Rev Lett. 2020 Oct 30;125(18):187702. doi: 10.1103/PhysRevLett.125.187702.
It has been argued that fluctuations of fermion parity are harmful for the demonstration of non-Abelian anyonic statistics. Here, we demonstrate a striking exception in which such fluctuations are actively used. We present a theory of coherent electron transport from a tunneling tip into a Corbino geometry Josephson junction where four Majorana bound states (MBSs) rotate. While the MBSs rotate, electron tunneling happens from the tip to one of the MBSs thereby changing the fermion parity of the MBSs. The tunneling events in combination with the rotation allow us to identify a novel braiding operator that does not commute with the braiding cycles in the absence of tunneling, revealing the non-Abelian nature of MBSs. The time-averaged tunneling current exhibits resonances as a function of the tip voltage with a period that is a direct consequence of the interference between the noncommuting braiding operations. Our work opens up a possibility for utilizing parity nonconserving processes to control non-Abelian states.
有人认为，费米子宇称的涨落不利于非阿贝尔任意子统计的证明。在此，我们展示了一个引人注目的例外情况，即这种涨落被积极利用。我们提出了一种从隧穿尖端到四个马约拉纳束缚态（MBS）旋转的科贝诺几何约瑟夫森结的相干电子输运理论。当MBS旋转时，电子从尖端隧穿到其中一个MBS，从而改变MBS的费米子宇称。隧穿事件与旋转相结合，使我们能够识别一个新的编织算符，它在没有隧穿时与编织循环不对易，揭示了MBS的非阿贝尔性质。时间平均隧穿电流作为尖端电压的函数呈现出共振，其周期是由非对易编织操作之间的干涉直接导致的。我们的工作为利用宇称不守恒过程来控制非阿贝尔态开辟了一种可能性。
