Quantum Oscillation of Thermally Activated Conductivity in a Monolayer WTe${}_2$-like Excitonic Insulator

Abstract

Recently, quantum oscillation of the resistance in insulating monolayer WTe${}_2$ was reported. An explanation in terms of gap modulation in the hybridized Landau levels of an excitonic insulator was also proposed by one of us. However, the previous picture of gap modulation in the Landau levels spectrum was built on a pair of well nested electron and hole Fermi surfaces, while the monolayer WTe${}_2$ has one hole and two electron Fermi pockets with relative anisotropy. Here we demonstrate that for system like monolayer WTe${}_2$, the excitonic insulating state arising from the coupled one hole and two electron pockets possesses a finite region in interaction parameter space that shows gap modulation in a magnetic field. In this region, the thermally activated conductivity displays the $1/B$ periodic oscillation and it can further develop into discrete peaks at low temperature, in agreement with the experimental observation. We show that the relative anisotropy of the bands is a key parameter and the qunatum oscillations decrease rapidly if the anisotropy increases further than the realistic value for monolayer WTe${}_2$.

6 pages, 3 figures. 9 pages of supplemental material. Comments are welcome

References in corpus (6)

• Quantum Spin Hall Effect and Topological Field Effect Transistor in Two-Dimensional Transition Metal Dichalcogenides
• Observation of the Quantum Spin Hall Effect up to 100 Kelvin in a Monolayer Crystal
• Quantum Oscillations of Electrical Resistivity in an Insulator
• Excitons in topological Kondo insulators - theory of thermodynamic and transport anomalies in SmB${}_6$
• Perfect charge compensation in WTe2 for the extraordinary magnetoresistance: From bulk to monolayer
• Anomalous Quantum Oscillations of Interacting Electron-hole Gases in Inverted Type-II InAs/GaSb Quantum Wells

Cited by in corpus (13)

• A New Era of Excitonic Insulators
• Quantum oscillations in interaction-driven insulators
• Quantum oscillations in 2D insulators induced by graphite gates
• Theory of Difference Frequency Quantum Oscillations
• Quantum Oscillations in the Magnetisation and Density of States of Insulators
• Electronic Density of States of a $U\left(1\right)$ Quantum Spin Liquid with Spinon Fermi Surface. I. Orbital Magnetic Field Effects
• Charge-Neutral Electronic Excitations in Quantum Insulators
• Theory of Glide Symmetry Protected Helical Edge States in WTe${}_2$ Monolayer
• Fluctuation-dominated quantum oscillations in excitonic insulators
• Quantum oscillations in field-induced correlated insulators of a moiré superlattice
• Quantum Oscillations in an Impurity-Band Anderson Insulator
• The Detection of Unconventional Quantum Oscillations in Insulating 2D Materials
• Magnetic-field effect on excitonic condensation emergent in extended Falicov-Kimball model