Majorana state in a pinned vortex at the surface of a topological insulator with proximity induced superconductivity in a magnetic field

The metallic surface states of a strong topological insulator become superconducting with the proximity of an s-wave superconductor. Due to the magnetic field the states undergo Landau quantization. A zero-energy Majorana state arises for the Landau level n=0 together with an equally spaced sequence of fermion excitations. The spin-momentum locking due to the Rashba spin-orbit coupling is key to the formation of the Majorana state. The local density of states for the bound states and their spin-polarization is obtained.