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arXiv · 1808.09893

Excitons without effective mass: biased bilayer graphene

Pengke Li·Ian Appelbaum
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Abstract

Understanding the dynamics of excitons in two dimensional semiconductors requires a theory that incorporates the essential physics distinct from their three-dimensional counterparts. In addition to the modified dielectric environment, single-particle states with strongly non-parabolic dispersion appear in many two-dimensional band structures, so that "effective mass" is ill-defined. Focusing on electrostatically-biased bilayer graphene as an example where quartic (and higher) dispersion terms are necessary, we present a semi-analytic theory used to investigate the properties of ground and excited excitonic states. This includes determination of relative oscillator strengths and magnetic moments (g-factors) which can be directly compared to recent experimental measurements.

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Pengke Li, Ian Appelbaum. 2018-08-29. Excitons without effective mass: biased bilayer graphene. https://doi.org/10.1103/physrevb.99.035429

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