Quantum Oscillation in Excitonic Insulating Electron-Hole Bilayer

Yuelin Shao; Xi Dai

doi:10.1103/physrevb.109.155107

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arXiv · 2401.01605

Quantum Oscillation in Excitonic Insulating Electron-Hole Bilayer

Yuelin Shao·Xi Dai

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Abstract

We study the quantum oscillations of inter-layer capacitance in an excitonic insulating electron-hole double layer with the Hartree Fock mean-field theory. Such oscillations could be simply understood from the physical picture ``exciton formed by electron/hole Landau levels'', where the direct gap between the electron-hole Landau levels will oscillate with exciton chemical potential and the inverse of the magnetic field. We also find that the excitonic order parameters can be destroyed by a strong magnetic field. At this time, the system becomes two independent quantum Hall liquids and the inter-layer capacitance oscillates to zero at zero temperature.

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Yuelin Shao, Xi Dai. 2024-01-03. Quantum Oscillation in Excitonic Insulating Electron-Hole Bilayer. https://doi.org/10.1103/physrevb.109.155107

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