Transport properties of Aharonov-Bohm ring with superconducting bridge

Sergey Aksenov


We have considered the Aharonov-Bohm ring which contains superconducting wire with Rashba spin-orbit interaction as a bridge connecting the arms. Using the nonequilibrium Green’s function technique and tight-binding approach transport properties of the device were calculated in linear-response regime. It was shown that the in-plane magnetic-field dependence of conductance has two types of resonance features. If the bridge is in topologically trivial phase and its lowest excitation energy is nonzero the conventional Breit-Wigner peaks defined by the arm energy emerge. When the bridge phase changes to the nontrivial one the Fano resonances appear as a result of the interference of Majorana and arm transport channels. The width of such resonances substantially depends on the degree of localization of the Majorana state. Thus, the considered device can be used to detect these states. Additionally, the effect of Aharonov-Bohm phase on the Fano resonances was analyzed.