Hallmarks of Majorana mode leaking into a hybrid double quantum dot

Abstract

We investigate the spectral and transport properties of a double quantum dot laterally attached to a topological superconducting nanowire, hosting the Majorana zero-energy modes. Specifically, we consider a geometry, in which the outer quantum dot is embedded between the external normal and superconducting leads, forming a circuit. First, we derive analytical expressions for the bound states in the case of an uncorrelated system and discuss their signatures in the tunneling spectroscopy. Then, we explore the case of strongly correlated quantum dots by performing the numerical renormalization group calculations, focusing on the interplay and relationship between the leaking Majorana mode and the Kondo states on both quantum dots. Finally, we discuss feasible means to experimentally probe the in-gap quasiparticles by using the Andreev spectroscopy based on the particle-to-hole scattering mechanism.

Andreev reflection mediated by Majorana zero modes in T-shaped double quantum dots

“…Some interesting phenomena were then found, such as half of the quantum value of the electron conductance [19] and sign reversion of the thermopower [20 -22]. There were also some works concerning MZMs hybridized to QDs with metallic and superconductor leads [23][24][25]. It was found that in the absence of the intradot Coulomb interaction, there is destructive (constructive) interference for spin-up (spin-down) electrons at the in-gap states.…”