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arXiv · 1410.0864

Metastable electron-electron states in double-layer graphene structures

Lachlan L. Marnham·Andrey V. Shytov
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Abstract

The prototypical exciton model of two interacting Dirac particles in graphene was analyzed in [1] and it was found that in one of the electron-hole scattering channels the total kinetic energy vanishes, resulting in a singular behaviour. We show that this singularity can be removed by extending the quasiparticle dispersion, thus breaking the symmetry between upper and lower Dirac cones. The dynamics of an electron-electron pair are then mapped onto that of a single particle with negative mass and anisotropic dispersion. We show that the interplay between dispersion and repulsive interaction can result in the formation of bound, Cooper-pair-like, metastable states in double-layered hybrid structures.

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Lachlan L. Marnham, Andrey V. Shytov. 2015-11-01. Metastable electron-electron states in double-layer graphene structures. https://doi.org/10.1103/physrevb.92.085409

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