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arXiv · 2002.11799

Gate-defined, Accumulation-mode Quantum Dots in Monolayer and Bilayer WSe$_2$

S. Davari·J. Stacy·A. M. Mercado·J. D. Tull·R. Basnet·K. Pandey·K. Watanabe·T. Taniguchi·J. Hu·H. O. H. Churchill
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Abstract

We report the fabrication and characterization of gate-defined hole quantum dots in monolayer and bilayer WSe$_2$. The devices were operated with gates above and below the WSe$_2$ layer to accumulate a hole gas, which for some devices was then selectively depleted to define the dot. Temperature dependence of conductance in the Coulomb blockade regime is consistent with transport through a single level, and excited state transport through the dots was observed at temperatures up to 10 K. For adjacent charge states of a bilayer WSe$_2$ dot, magnetic field dependence of excited state energies was used to estimate $g$-factors between 0.8 and 2.4 for different states. These devices provide a platform to evaluate valley-spin states in monolayer and bilayer WSe$_2$ for application as qubits.

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S. Davari, J. Stacy, A. M. Mercado, J. D. Tull, R. Basnet, K. Pandey, K. Watanabe, T. Taniguchi, J. Hu, H. O. H. Churchill. 2020-02-26. Gate-defined, Accumulation-mode Quantum Dots in Monolayer and Bilayer WSe$_2$. https://doi.org/10.1103/physrevapplied.13.054058

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