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arXiv · 2110.11330

Interaction range and temperature dependence of symmetry breaking in strongly correlated two-dimensional moir\'e transition metal dichalcogenide bilayers

Haining Pan·Sankar Das Sarma
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Abstract

We theoretically consider two-dimensional moir\'e transition metal dichalcogenide (TMD) bilayers, which are strongly correlated in the sense that the on-site Coulomb interaction is comparable to or larger than the hopping kinetic energy between the moir\'e lattice sites. The system accommodates many symmetry-broken ground states both in charge and isospin sectors at various commensurate rational fillings such as 1/2, 1/3, 1/4, 2/3, etc. We investigate two complementary important aspects of the dependence of the symmetry breaking on (1) the range of the electron-electron interaction, which can in principle be experimentally controlled by the nearby gates and the dielectric environment, and (2) temperature, which could thermally suppress the symmetry breaking above a critical temperature. Experimental implications of the theory are discussed.

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Haining Pan, Sankar Das Sarma. 2021-10-21. Interaction range and temperature dependence of symmetry breaking in strongly correlated two-dimensional moir\'e transition metal dichalcogenide bilayers. https://doi.org/10.1103/physrevb.105.041109

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