Hybrid metal-semiconductor quantum dots in InAs as a platform for quantum simulation

Abstract Arrays of hybrid metal-semiconductor quantum dots offer a new approach to quantum simulation, with key advantages over arrays of conventional quantum dots. Because the metallic component of these hybrid dots has a quasi-continuous level spectrum, each site in an array can be effectively electronically identical; in contrast, each conventional semiconductor quantum dot has its own spectral fingerprint. Meanwhile, the semiconductor component retains gate-tunability of intersite coupling. This combination creates a scalable platform for simulating correlated ground states driven by Coulomb interactions. We report the fabrication and characterization of hybrid metal-semiconductor dots, featuring a submicron metal island transparently contacting a gate-confined region of an InAs quantum well with tunable couplings to macroscopic leads. Tuning the dot-lead coupling to the weak-coupling limit yields highly-uniform Coulomb peaks, with no resolvable excitation spectrum in the Coulomb diamonds. We propose a realistic device design for a hybrid dot-based linear array quantum simulator and outline the correlated many-body physics accessible in this architecture.