Electrical Properties of Selective-Area-Grown Superconductor-Semiconductor Hybrid Structures on Silicon

We present a superconductor-semiconductor materials system that is both scalable and monolithically integrated on silicon substrate. It uses selective-area growth of $\mathrm{Al}$-$\mathrm{In}\mathrm{As}$ hybrid structures planar III-V buffer layer, grown directly high-resistivity characterize the electrical properties this at millikelvin temperatures observe high average field-effect mobility $\ensuremath{\mu}\ensuremath{\approx}3200\phantom{\rule{0.2em}{0ex}}{\mathrm{cm}}^{2}\mathrm{/Vs}$ for $\mathrm{In}\mathrm{As}$ channel hard induced superconducting gap. Josephson junctions exhibit interface transmission, $\mathcal{T}\ensuremath{\approx}0.75$, gate-voltage-tunable switching current with product critical normal state resistance, ${I}_{C}{R}_{N}\ensuremath{\approx}83\phantom{\rule{0.2em}{0ex}}\ensuremath{\mu}\mathrm{V}$, signatures multiple Andreev reflections. These results pave way high-coherence transmon devices other hybrids fabricated silicon.