Séminaire de groupe
|Majorana and Andreev bound states in topological wires in the proximity of superconductors|
|jeudi 07 mars 2013 , 10h25|
|Salle de séminaire du groupe de Physique Statistique|
We study one-dimensional topological SN and SNS long junctions obtained by placing a topological insulating nanowire in the proximity of either one or two SC finite-size leads. Using the Majorana Polarization order parameter we find that for a finite-size SN junction the ABS spectrum exhibits a zero-energy extended state which carries a full Majorana fermion, while the ABS of long SNS junctions with a phase difference of pi transform into two zero-energy states carrying two Majorana fermions with the same MP. We also study the effects of finite SC penetration depths in such junctions. Last but not least we analyze a more realistic model for the coupling between a superconducting substrate and a topological wire, the resulting proximity effect, and the role played by the Andreev bound states in the topological wire in such a setup.