报告题目：Transport and fusion of Majorana zero modes in the presence of nonadiabatic transitions

报告人：冯伟 副教授（天津大学）

报告时间：2024年11月29日（周五） 14：00-15：00

报告地点：北洋园校区49教410室

报告摘要：

      The nonlocal nature of the Majorana zero modes (MZMs) and non-Abelian statistics obeyed provide an elegant paradigm of topological quantum computation. Probing the underlying non-Abelian statistics, via either braiding or fusion, is an essential step in identifying MZMs through experiments. In this talk, I will report results of simulations for transport and nontrivial fusion of Majorana zero modes in topological superconducting quantum wires. We uncover interesting behaviors of nonadiabatic transition associated with the transport through mini-gate-controlled multiple-segment modulations. Owing to breaking of the initial fermion parity induced by nonadiabatic transitions, a deviation from the statistics of outcomes of nontrivial fusion arises and is analyzed. Moreover, we develop a measurement scheme to infer the amount of fermion parity breaking and nonadiabatic transition probability to excited states, based on the characteristic spectrum of measurement current by a quantum-point-contact detector, by measurement of the charge occupation dynamics in a fusion-outcome-probing quantum dot.

参考文献：

[1] J. F. Steiner and F. von Oppen, Readout of Majorana qubits, Phys. Rev. Research 2, 033255 (2020).

[2] T. Zhou, M. C. Dartiailh, K. Sardashti, J. E. Han, A. Matos-Abiague, J. Shabani, and I.  Zutic, Fusion of Majorana bound states with mini-gate control in two-dimensional systems, Nat. Commun. 13, 1738 (2022).

[3] J. Bai, Q. Wang, L. Xu, W. Feng, and X.-Q. Li, Phys. Rev. B 109, 085403 (2024).

[4] Q. Wang, J. Bai, L. Xu, W. Feng, and X.-Q. Li, Phys. Rev B 110, 115402 (2024).

报告人简介：

      冯伟，2009年，北京师范大学物理系获学士学位；2014年，北京师范大学物理系获博士学位。2014年起，天津大学理学院工作。2018年-2019年，赴澳大利亚RMIT大学国家公派访问。研究方向主要包括量子测量、量子信息和量子计算。