Excitons without effective mass: biased bilayer graphene

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.

arXiv commentSM upon request

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Cited by in corpus (10)

• Theoretical methods for excitonic physics in two-dimensional materials
• Absorption and optical selection rules of tunable excitons in biased bilayer graphene
• Tunable Excitons in Rhombohedral Trilayer Graphene
• Anisotropic linear and non-linear excitonic optical properties of buckled monolayer semiconductors
• Dynamical screening and excitonic bound states in biased bilayer graphene
• Tunable nonlinear excitonic optical response in biased bilayer graphene
• Canted antiferromagnetism and excitonic order in gated double-layer graphene
• Tunable exciton polaritons in biased bilayer graphene
• Excitonic instability in transition metal dichalcogenides
• Contribution to Excitonic Linewidth from Free Carrier-Exciton Scattering in Layered Materials: The example of h-BN