Two-dimensional crystals consisting of single layers of atomsare modern materials that can be used for implementation of quantum computation. 2D monolayers of transitionmetal dichalcogenides, e.g. MoS2, seem to be better... [ view full abstract ]
Two-dimensional crystals consisting of single layers of atomsare modern materials that can be used for implementation of quantum computation. 2D monolayers of transitionmetal dichalcogenides, e.g. MoS2, seem to be better candidates than graphene because they have wide band gaps and strong electrically induced spin-orbit coupling of the Rashba type [1,2]. Considering the valley degree of freedom of an electron together with its spin extends the ability to define a qubit into: spin, valley and hybrid spin-valley qubit [3]. However, the most interesting is the definition based on spin and valley of a single electron as a two qubit system [4,5].
We propose a nanodevice based on a gate-defined quantum dot within a MoS2monolayer in which we confine a single electron. By applying control voltages to the device gates we modulate the confinement potential and force inter-valley transitions [6]. The present Rashba spin-orbit coupling additionally allows for spin operations as well as the spin-valley swap. By performing numerical simulations, we show how by electrically controlling the state of the electron in such a device, we can obtain single- and two-qubit (thus universal) gates in the spin-valley two-qubit system.
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Quantum information processing and computing , Solid states and hybrid systems
