Doped t-J model of twisted bilayer WSe2

Document Type : Original Article

Authors

1 Department of Physics, Qom University of Technology, Qom, Iran

2 Department of Physics, Faculty of Science, Shahrekord University, Shahrekord, Iran

Abstract

Experiments in twisted materials have shown evidence of exotic phases, such as correlated insulating phases and unconventional superconductivity states. Recently, the topological moiré valance bands with opposite Chern numbers in twisted bilayer WSe  have been described with a generalized Kane-Mele model on a honeycomb lattice. Interaction strength, band filling, and bandwidth of twisted materials are well controlled employing varying the twist angle and using three-dimensional dielectric environments. To describe the existence of these exotic phases in the twisted bilayer WSe , we consider the doped moiré Hubbard model in the strongly correlated limit. Here, we are interested in studying the stability of different superconductivity channels by employing the mean-filed theory. We find that the admixture of the nearest-neighbor- - and next-nearest-neighbor- -wave pairings is the superconducting ground state at any doping level. In addition, the obtained results show that the quasi-spin-orbit interaction plays an essential role in the stability of this mixed singlet-triplet superconductivity.

Keywords

Main Subjects

© 2023 The Author(s). Journal of Progress in Physics of Applied Materials published by Semnan University Press. This is an open access article under the CC-BY 4.0 license. (https://creativecommons.org/licenses/by/4.0/)

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Progress in Physics of Applied Materials
Volume 3, Issue 2 - Serial Number 5
December 2023
Pages 125-130

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History

  • Receive Date: 26 November 2023
  • Revise Date: 10 December 2023
  • Accept Date: 16 December 2023

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