Time-resolved Charge Detection in Transition Metal Dichalcogenide Quantum Dots

TL;DR

This paper demonstrates time-resolved charge detection in MoS₂ quantum dots, enabling access to the few-electron regime and single-electron tunneling events, advancing quantum information applications.

Contribution

It introduces a charge detection method for MoS₂ quantum dots, revealing the crossover from single to double quantum dots and enabling single-shot spin and valley readout.

Findings

Resolved individual tunneling events in MoS₂ quantum dots.

Observed crossover from single to double quantum dot regimes.

Established potential for quantum information processing.

Abstract

We investigate electronic transport through gate-defined quantum dots in molybdenum disulfide MoS$_2$ using an integrated charge detector. We observe a crossover from two weakly coupled single dots to a strongly coupled double quantum dot. In the regime of extremely weak dot-lead coupling, where the direct transport current is below the detection limit, we measure the dot occupation via charge detection and access the few-electron regime. Due to the large band gap of MoS$_2$, tunneling rates can be sufficiently suppressed to resolve individual tunneling events. These results establish a platform for single-shot spin- and valley-to-charge conversion and highlight the potential of transition-metal dichalcogenide quantum dots for quantum information applications.