laboratoire pierre aigrain
électronique et photonique quantiques
laboratoire pierre aigrain

Séminaire, 12 Mai 2014

Vic Kam Teun Law (HKUST)
Majorana fermion induced Equal Spin Andreev reflections

t has been shown theoretically that Majorana fermions induce resonant Andreev reflections and cause zero bias conductance peaks (ZBCP) in electron spectroscope measurements. The Majorana induced ZBCP has been possibly observed in semi-conductor/superconductor heterostructures but the origin of the ZBCP is still under debate.

In this talk, we show that Majorana fermions induce a special type of Andreev reflection processes whereby electrons with certain spin polarization are reflected as holes with the same spin. On the other hand, electrons with opposite spin cannot undergo Andreev reflections and are reflected as electrons [1]. We call these processes Majorana fermion induced selective equal spin Andreev reflections (SESARs). We show that SESARs can be used to detect Majorana fermions. In a related work, we show that Majorana fermions in a special type of BDI class topological superconductors can be used to generate correlated spin-polarized currents [2].

[1] J. He, T. K. Ng, P. A. Lee and K. T. Law, Phys. Rev. Lett. 112, 037001 (2014).
[2] J. He, J. S. Wu, T.P. Choy, X. J. Liu, Y. Tanaka and K. T. Law, Nat. Comm. 5:3232 (2014).