Integration of superconducting NbN thin films with III-Nitride semiconductors*

The superconducting properties of metallic NbN have been known and studied for several decades, but it has been successfully integrated epitaxially with the Gallium Nitride family of wide-bandgap semiconductors only recently. In this work, we report the physical properties of epitaxial NbN integrated with SiC, AlN, and GaN grown by molecular beam epitaxy. We study the crystallinity, surface and interface qualities of the superconductor/semiconductor heterojunctions, and the superconducting properties (critical temperatures of ~16K, coherence lengths of ~10nm, and critical Meissner fields in excess of 35T) of epitaxial NbN. Progress towards the realization of all-epitaxial NbN/Semiconductor heterojunctions, superconductors integrated with nitride transistors, and epitaxial Josephson junctions, all towards establishing a fundamentally new platform for superconducting electronics will be presented.