InSb Nanostructures for Advanced Quantum Devices

Indium-antimonide (InSb) nanowires (NWs) constitute a suitable platform for hosting Majorana zero modes, a key requirement for fault-tolerant topological quantum computing, due to their high electron mobility and strong spin-orbit coupling.
Building devices based on InSb nanostructures, while maintaining their pristine quality has proven to be rather challenging. Firstly, brought forth by the difficulties to obtain high quality nanostructures and secondly due to the fabrication steps required to transform a single nanostructure into a working device.
Here, we show the growth of pure zinc blende InSb NWs and nanosheets. The high chemical purity of these nanostructures is reflected in the higher electron mobility values as compared to so far reported values for InSb nanostructures. Further, we use the high degree of control over growing both 1-dimensional (1D) and 2-dimensional (2D) nanostructures on the same substrate, to design in-situ quantum device structures. In particular, by relying on both InSb NWs and nanosheets to shadow deposit superconductors and normal metals we design a variety of devices ranging from Josephson Junctions to hybrid superconductor/semiconductor devices, while circumventing the harsh processing steps which degrade the device quality.