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arXiv · 1004.5471

Exciton condensation and fractional charge in a bilayer two-dimension electron gas adjacent to a superconductor film

Ningning Hao·Ping Zhang·Jian Li·Wei Zhang·Yupeng Wang
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Abstract

We study the exciton condensate (EC) in a bilayer two-dimension-electron-gas (2DEG) adjacent to a type-II superconductor thin film with an array of pinned vortex lattices. By applying continuum low energy theory and carrying numerical simulations of lattice model within mean-field approximation, we find that if the order parameter of EC has a vortex profile, there are exact zero modes and associated \emph{rational} fractional charge for zero pseudospin potential ($μ$) and average chemical potential ($h$): $μ$=0 and $h$=0; while for $μ\mathtt{\neq}0$ and $h$=0, intervalley mixing splits the zero energy levels, and the system exhibits \emph{irrational} fractional \emph{axial} charge.

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Ningning Hao, Ping Zhang, Jian Li, Wei Zhang, Yupeng Wang. 2010-04-30. Exciton condensation and fractional charge in a bilayer two-dimension electron gas adjacent to a superconductor film. https://doi.org/10.1103/physrevb.82.165317

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