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Updated: May 16, 2025

A Standard and Reliable Method to Fabricate Two-Dimensional Nanoelectronics
Published on: August 28, 2018
Single electron quantum dot in two-dimensional transition metal dichalcogenides
Jarosław Pawłowski1, Pankaj Kumar2,3, Kenji Watanabe4
1Institute of Theoretical Physics, Wrocław University of Science and Technology, Wrocław, Poland.
Abstract:
Spin-valley properties in two-dimensional (2D) semiconducting transition metal dichalcogenides (TMDCs) has attracted significant interest due to the possible applications in quantum computing. Spin-valley properties can be exploited in TMDC quantum dot (QD) with well-resolved energy levels. This requires smaller QDs, especially in material systems with heavy carrier effective mass e.g. TMDCs and silicon. Device architectures employed for TMDC QDs so far have difficulty achieving smaller QDs. Therefore, an alternative approach in the device architecture is needed. Here, we propose a multilayer device architecture to achieve a gate-defined QD in TMDC with a relatively large energy splitting on the QD. We provide a range of device dimensions and dielectric thicknesses and its correlation with the QD energy splitting. The device architecture is modeled realistically. Moreover, we show that all the device parameters used in modeling are experimentally achievable. These studies lay the foundation for future work toward spin-valley qubits in TMDCs. The successful implementation of these device architectures will drive the technological development of 2D materials-based quantum technologies.
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