We consider microwave spectroscopy of Josephon junctions composed of hybridized Majorana states in topological 1-D superconductors. We point out how spectroscopic features of the junction appear in the current phase relation under microwave irradiation. Moreover, we discuss a way to directly probe the nonequilibrium state associated with the 4{\pi} periodic Josephson effect. In particular, we show how the microwave driving can be used to switch from a 4{\pi} to a 2{\pi} Shapiro step in the current voltage relation.
@article{arxiv.1303.2353,
title = {Microwave spectroscopy of Josephson junctions in topological superconductors},
author = {Pauli Virtanen and Patrik Recher},
journal= {arXiv preprint arXiv:1303.2353},
year = {2013}
}