Bottom gated in-plane InSb nanostructures on GaAs(111)B grown by selective area epitaxy

This work presents a method of achieving high-quality in-plane InSb nanowires on a highly mismatched GaAs (111)B substrate through the combination of atomic hydrogen-assisted selective area molecular beam epitaxy and extreme Sb-rich conditions. By inserting an InGaP barrier layer on top of the substrate used as a back-gate control, we show the modulation of the conductivity in InSb thin films, selective area-grown in-plane platelets and nanowires. The linear conductance of the InSb nanowires grown along three major in-plane crystal orientations is probed with multi-probe scanning tunnelling microscopy to extract the field-effect electron mobility, its magnitude being compared with the study of defects in the nanowires. These results provide an additional level of control for the fabrication of advanced quantum devices using selective area grown in-plane InSb nanostructures.