拓扑超导体中的经典自旋

When topological order is realized in a certain class of superconductors,Majorana fermions can be supported on the edge or in the vortex coreresting with the time-reversal symmetry, which play an important role for the realization offault-tolerant topological quantum computation. In this work, we proposea scheme to distinguish topological superconducting from normal superconductingstates by measuring the number of impurity-induced in-gap bound states.It is shown that there are always four in-gap bound states in topologicalsuperconducting states induced by magnetic impurities, and two by nonmagnetic impurities,irrelevant of the impurity strength. However, onlytwo in-gap bound states are induced in normal superconductingstates when impurity strength is weak. Our results help withthe search of topological order in superconductors without resorting tothe surface modes.