Valley Two-Qubit System in a MoS2-Monolayer Gated Double Quantum dot

This study addresses two hot topics in condensed matter physics: quantum computing and valleytronics. The authors propose a solid-state qubit exploiting the electronic valley degree in a monolayer transition-metal dichalcogenide (TMDC). Simulations show how to obtain single- and two-qubit gates in the valley two-qubit system by electrically controlling the state and the coupling between the two electrons confined in a gated double-quantum-dot structure. Both single- and two-qubit operations are explained, as well as initialization and readout. Thus the team obtains a physical scheme for universal quantum computing based on the valley isospin in gate-defined TMDC double quantum dots.