MSc-seminar: Andreev bound states in Josephson junctions of nodal superconductors in a ribbon geometry

by Mr. Gal Cohen

Physics department, BGU

at Condensed Matter Seminar

Mon, 04 Mar 2024, 11:10
Sacta-Rashi Building for Physics (54), room 207

Abstract

Transition metal dichalcogenides (TMDs) offer a unique platform to study unconventional superconductivity(SC), with a a strong spin orbit coupling and stability to an in-plane magnetic field. In particular a recent study shows that when the in plane field exceeds the Pauli limit, a nodal SC phase appear, those nodal SC phase hosts Majorana flat band.
In a Josephson junction setup, the nodal phase is associated with a current phase relation which depends on the momentum transverse to the channel and for certain values can show 4$\pi$ periodicity. In this proposal we will add another term to our Hamiltonian, the Rashba spin orbit coupling. This yield an interesting phenomena on the topological nodal superconducting phase. Without Rashba spin orbit coupling we witness 12 nodal points of 6 pairs in our model, 8 of them are the lines $\pm\sqrt{3}k_y=k_x$ and the other 4 are for $k_x=0$ line. Adding a very small Rashba term lifts the 8 nodal, while the other 4 nodal points remain stable.
We study the current-phase relation of this nodal superconductor in a Josephson junction geometry.
The calculations in this research could further the applications of new superconducting devices and quantum computing, moreover the search of Majorana particle.

Created on 26-02-2024 by Naamneh, Muntaser (mnaamneh)
Updaded on 29-02-2024 by Naamneh, Muntaser (mnaamneh)