Wigner crystallization in transition metal dichalcogenides: A new approach to correlation energy

Abstract

We introduce a new approach for the correlation energy of one- and two-valley two-dimensional electron gas (2DEG) systems. Our approach is based on a random phase approximation at high densities and a classical approach at low densities, with interpolation between the two limits. This approach gives excellent agreement with available Quantum Monte Carlo (QMC) calculations. We employ the two-valley 2DEG model to describe the electron correlations in monolayer transition metal dichalcogenides (TMDs). The zero-temperature transition from a Fermi liquid to a quantum Wigner crystal phase in monolayer TMDs is obtained using density-functional theory within the local-density approximation. Consistent with QMC, we find that electrons crystallize at $r_s=30.5$ in one-valley 2DEG. For two-valleys, we predict Wigner crystallization at $r_s=29.5$, indicating that valley degeneracy has little effect on the critical $r_s$, in contrast to an earlier claim.

5 pages, 3 figures

References in corpus (4)

• The electronic properties of graphene
• The Valley Hall Effect in MoS2 Transistors
• Phase Diagram of the Low-Density Two-Dimensional Homogeneous Electron Gas
• Surface Charge Density Wave Transition in NbSe${}_3$

Cited by in corpus (17)

• Observation of Wigner crystal of electrons in a monolayer semiconductor
• Optical properties of charged excitons in two-dimensional semiconductors
• Generalized Wigner crystallization in moiré materials
• Landau-quantized excitonic absorption and luminescence in a monolayer valley semiconductor
• Sublattice structure and topology in spontaneously crystallized electronic states
• Tunable quantum criticalities in an isospin extended Hubbard model simulator
• Wigner Crystals in Two-Dimensional Transition-Metal Dichalcogenides: Spin Physics and Readout
• Crossover from exciton polarons to trions in doped two-dimensional semiconductors at finite temperature
• Terahertz fingerprint of monolayer Wigner crystals
• Nanomechanical spectroscopy of 2D materials
• Valley and spin polarized broken symmetry states of interacting electrons in gated MoS${}_2$ quantum dots
• Wigner crystallization of electrons in a one-dimensional lattice: a condensation in the space of states
• Rich many-body phase diagram of electrons and holes in doped monolayer transition metal dichalcogenides
• Exact Quantum Virial Expansion for the Optical Response of Doped Two-Dimensional Semiconductors
• Competition of Exchange and Correlation Energies in Two-Dimensional $N$-component Electron Gas Ferromagnetism
• Importance of electron-phonon coupling near the electron-liquid to Wigner-crystal transition in two-dimensional atomically thin materials
• Energy spectrum and structure of one-dimensional few-electron Wigner crystals with and without coupling to light in cavity