Topological superconductivity in chromium dioxide heterostructures

Heterostructures of chromium dioxide and titanium dioxide were recently predicted to support a spin polarized 2D Dirac electronic phase. Due to the presence of spin-orbit coupling, the system opens a gap, forming a Chern insulator. In this work, we investigate the development of intrinsic triplet superconductivity in this system. Based on crystal symmetries of the heterostructure, we show that attractive interactions can produce p+ip superconductivity. Performing calculations on the lattice at the mean field level, we find that the system has a sequence of topological phase transitions as a function of the chemical potential, which can be tuned with a gate voltage. Among several different phases, we identity a chiral topological phase having a single Majorana mode at the edge. We calculate the spectroscopic signatures for the edge modes in this system.