Vortex lattice states of bilayer electron-hole fluids in quantizing magnetic fields

Bo Zou; Allan H. MacDonald

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arXiv · 2411.08810

Vortex lattice states of bilayer electron-hole fluids in quantizing magnetic fields

Bo Zou·Allan H. MacDonald

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Abstract

We show that the ground state of a weakly charged two-dimensional electron-hole fluid in a strong magnetic field is a broken translation symmetry state with interpenetrating lattices of localized vortices and antivortices in the electron-hole-pair field. The vortices and antivortices carry fractional charges of equal sign but unequal magnitude and have a honeycomb lattice structure that contrasts with the triangular lattices of superconducting electron-electron-pair vortex lattices. We predict that increasing charge density or weakening magnetic field drives a vortex delocalization transition that would be signaled experimentally by an abrupt increase in counterflow transport resistance.

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Bo Zou, Allan H. MacDonald. 2024-11-13. Vortex lattice states of bilayer electron-hole fluids in quantizing magnetic fields. https://arxiv.org/abs/2411.08810

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