Affiliation:
1. School of Electronic and Information Engineering, UEST of China, Zhongshan Institute, Zhongshan 528400, China
2. College of Science, North China Institute of Science and Technology, Beijing 101601, China
Abstract
We investigate theoretically the Josephson current through one semiconductor quantum dot (QD) coupled to triple nanowires (junctions) with Majorana bound states (MBSs) prepared at their ends. We find that not only the strength but also the period of the Josephson current flowing between the left and right Josephson junctions via the dot can be fully controlled in terms of the third junction side-coupled to the QD. When the phase factor is zero in the third junction, which acts as a current regulator, the Josephson current is a 2π-period function of the difference in phases of the left and right junctions. Now, the magnitude of the current is suppressed by hybridization between the QD and the regulator junction. The period of the current becomes 4π under the condition of nonzero phase factor in the regular junction, and thus either the magnitude or the sign (flow direction) of the current can be controlled in this trijunction device. This is difficult to realize in the usual tow-terminal structure. It is also found that the direct overlap between the MBSs in the regulator junction generally enhances the current’s amplitude, but those in the left and right Majorana junctions suppress the current. The above results are explained with the help of the device’s energy diagram and the current carrying density of states (CCDOS) and might be applied for adjusting the current density in the superconducting coated conductors technologies.
Funder
Education Characteristic Innovation Project of the Department of Education in Guang-dong Province
Engineering Technology Research Center of Colleges and Universities in Guang-dong Province
Innovation Team of Colleges and Universities in Guang-dong Province
13th Five-Year Plan of Education Scientific Research Project of the Department of Education in Guang-dong Province
Educational Quality Project of the Department of Education in Guang-dong Province
Key Scientific Research Project of the Department of Education in Guang-dong Province
Subject
Materials Chemistry,Surfaces, Coatings and Films,Surfaces and Interfaces
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