High critical temperature nodal superconductors as building block for time-reversal invariant topological superconductivity

Abstract

We study possible applications of high critical temperature nodal superconductors for the search for Majorana bound states in the DIII class. We propose a microscopic analysis of the proximity effect induced by d-wave superconductors on a semiconductor wire with strong spin-orbit coupling. We characterize the induced superconductivity on the wire employing a numerical self-consistent tight-binding Bogoliubov-De-Gennes approach, and analytical considerations on the Green's funtion. The order parameter induced on the wire, the pair correlation function and the renormalization of the Fermi points are analyzed in detail, as well as the topological phase diagram in the case of weak coupling. We highlight optimal Hamiltonian parameters to access the non trivial topological phase which could display time-reversal invariant Majorana doublets at the boundaries of the wire.

Superconducting Proximity Effect in d‐Wave Cuprate/Graphene Heterostructures

“…[7] Furthermore, the combination of high-T C and the 𝜋 phase shift between d-wave lobes can be used for designing topological Josephson junction hosting Majorana bound states. [78][79][80] Although extended to different d-wave/s-wave Josephson junctions, [81] so far these 𝜋 junctions have not been explored using Dirac materials (and particularly graphene) as Josephson barrier. Yet, these devices would be endowed with an interesting property, namely tunability, by replacing the usual passive weak link by a gate-tunable Dirac material.…”

Majorana Corner Modes in a High-Temperature Platform

“…In addition, MKPs can be used as tunable generators of MZMs by breaking the TRS [57,58]. There have been a few interesting proposals for realizing TRI topological superconductors and MKPs [57,58,[72][73][74][75][76][77][78][79][80][81][82][83][84], though experimental realizations are yet to come.…”

Superconducting proximity effect in $d$-wave cuprate/ graphene heterostructures

“…One of the outstanding possibilities is the realization of junctions with a built-in π-shift between the electrodes, allowing for half-quantum superconducting loops [76] that enable novel rapid single flux quantum logic devices architectures with enhanced capabilities [7]. Furthermore, the combination of high-T C and the π phase shift between d-wave lobes can be used for designing topological Josephson junction hosting Majorana bound states [77,78,79].…”