Dr. Suk Bum Chung
Department of Physics
Stanford Institute for Theoretical Physics

Detecting Majorana boundary state of topological superconductor

Abstract:

The concept of the Majorana fermion has been postulated more than eighty years ago; however, this elusive particle has never been observed in nature. The non-local character of the Majorana fermion can be useful for topological quantum computation. Recently, it has been recognized that topological superconductors (TSC) can support gapless Majorana state at its boundary. First known examples of such TSC were the B phase of 3He superfluid in 3D and p_x + ip_y superconductor in 2D; more recent examples include proximity-induced s-wave superconductivity in a magnetically doped BiSe film. In my talk, I will discuss how we can experimentally detect the Majorana nature of gapless boundary state in these systems. One is the sharp dependence on the DC Zeeman field direction of resonance frequency and relaxation rate of impurity spin interacting with the Majorana boundary state. The other is by measuring conductance when topological superconductor induce Majorana backscattering. I will show that in this case, there is a experimentally accessible limit where Andreev and normal scattering has equal probability.