Phonon-induced exciton weak localization in two-dimensional semiconductors

Abstract

We study theoretically the contribution of quantum effects to the exciton diffusion coefficient in atomically thin crystals. It is related to the weak localization caused by the interference of excitonic wavefunctions on the trajectories with closed loops. Due to a weak inelasticity of the exciton-phonon interaction the effect is present even if the excitons are scattered by long-wavelength acoustic phonons. We consider exciton interaction with longitudinal acoustic phonons with linear dispersion and with flexural phonons with quadratic dispersion. We identify the regimes where the weak localization effect can be particularly pronounced. We also briefly address the role of free charge carriers in the exciton quantum transport and, within the self-consistent theory of localization, the weak localization effects beyond the lowest order.

12 pages, 5 figures

References in corpus (11)

• The Raman Fingerprint of Graphene
• k.p theory for two-dimensional transition metal dichalcogenide semiconductors
• Electron scattering on microscopic corrugations in graphene
• Theory of resonant multiphonon Raman scattering in graphene
• Phonon Sidebands in Transition Metal Dichalcogenides
• Nonclassical Exciton Diffusion in Monolayer WSe2
• Quantum elasticity of graphene: Thermal expansion coefficient and specific heat
• Flexuron, a self-trapped state of electron in crystalline membranes
• Interlayer exciton-polaron in atomically thin semiconductors
• Flexural deformations and collapse of bilayer two-dimensional crystals by interlayer exciton
• Spatiotemporal dynamics of free and bound excitons in CVD-grown MoS${}_2$ monolayer