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DOE OSTI · 1803851

Gate-Defined Accumulation-Mode Quantum Dots in Monolayer and Bilayer WSe 2

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

Here, we report the fabrication and characterization of gate-defined hole quantum dots in monolayer and bilayer WSe 2 . The devices are operated with gates above and below the WSe 2 layer to accumulate a hole gas, which for some devices is 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 is observed at temperatures up to 10 K. For adjacent charge states of a bilayer-WSe 2 dot, the magnetic field dependence of excited-state energies is used to estimate $\textit{g}$ 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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BibTeXRIS

Davari, S., Stacy, J., Mercado, A. M., Tull, J. D., Basnet, R., Pandey, K., Watanabe, K., Taniguchi, T., Hu, J., Churchill, H. O. H.. 2020-05-22. Gate-Defined Accumulation-Mode Quantum Dots in Monolayer and Bilayer WSe 2. https://doi.org/10.1103/physrevapplied.13.054058

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