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arXiv · 1909.00558

Molecular collapse in monolayer graphene

Robbe Van Pottelberge·Dean Moldovan·S. P. Milovanovic·Francois M. Peeters
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Abstract

Atomic collapse is a phenomenon inherent to relativistic quantum mechanics where electron states dive in the positron continuum for highly charged nuclei. This phenomenon was recently observed in graphene. Here we investigate a novel collapse phenomenon when multiple sub- and supercritical charges of equal strength are put close together as in a molecule. We construct a phase diagram which consists of three distinct regions: 1) subcritical, 2) frustrated atomic collapse, and 3) molecular collapse. We show that the single impurity atomic collapse resonances rearrange themselves to form molecular collapse resonances which exhibit a distinct quasi-bonding, anti-bonding and non-bonding character. Here we limit ourselves to a systems consisting of two and three charges. We show that by tuning the distance between the charges and their strength a high degree of control over the molecular collapse resonances can be achieved.

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Robbe Van Pottelberge, Dean Moldovan, S. P. Milovanovic, Francois M. Peeters. 2019-09-02. Molecular collapse in monolayer graphene. https://doi.org/10.1088/2053-1583%2Fab3feb

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