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arXiv · 1910.08420

Time scales for charge-transfer based operations on Majorana systems

R. Seoane Souto·K. Flensberg·M. Leijnse
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Abstract

In this article we analyze the efficiency of operations based on transferring charge from a quantum dot (QD) to two coupled topological superconductors, which can be used for performing nonabelian operations on Majorana bound states (MBSs). We develop a method which allows us to describe the full time-evolution of the system as the QD energy is manipulated. Using a full counting statistics analysis, we set bounds to the operation time scales. The lower bound depends on the superconducting phase difference due to a partial decoupling of the different MBSs parity sectors, while the upper bound is set by the tunneling of quasiparticles to the MBSs. Using realistic parameters, we find the existence of a regime where the operation can be carried out with a fidelity close to unity. Finally, we propose the use of a two operations protocol to quantify the effect of the dephasing and accumulated dynamical phases, demonstrating their absence for certain superconducting phase differences.

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R. Seoane Souto, K. Flensberg, M. Leijnse. 2019-10-18. Time scales for charge-transfer based operations on Majorana systems. https://doi.org/10.1103/physrevb.101.081407

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