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arXiv · 2106.15090

Spin-valley qubits in gated quantum dots in a single layer of transition metal dichalcogenides

Abdulmenaf Altıntaş·Maciej Bieniek·Amintor Dusko·Marek Korkusiński·Jarosław Pawłowski·Paweł Hawrylak
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Abstract

We develop a microscopic and atomistic theory of electron spin-based qubits in gated quantum dots in a single layer of transition metal dichalcogenides. The qubits are identified with two degenerate locked spin and valley states in a gated quantum dot. The two-qubit states are accurately described using a multi-million atom tight-binding model solved in wavevector space. The spin-valley locking and strong spin-orbit coupling result in two degenerate states, one of the qubit states being spin-down located at the $+K$ valley of the Brillouin zone, and the other state located at the $-K$ valley with spin up. We describe the qubit operations necessary to rotate the spin-valley qubit as a combination of the applied vertical electric field, enabling spin-orbit coupling in a single valley, with a lateral strongly localized valley-mixing gate.

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Abdulmenaf Altıntaş, Maciej Bieniek, Amintor Dusko, Marek Korkusiński, Jarosław Pawłowski, Paweł Hawrylak. 2021-10-07. Spin-valley qubits in gated quantum dots in a single layer of transition metal dichalcogenides. https://doi.org/10.1103/physrevb.104.195412

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