Phonon-assisted carrier motion on the Wannier-Stark ladder

Abstract

It is well known that at zero temperature and in the absence of electron-phonon coupling, the presence of an electric field leads to localization of carriers residing in a single band of finite bandwidth. We implement the Self-Consistent Born Approximation (SCBA) to study the effect of weak electron-phonon coupling on the motion of a carrier in a biased system. At moderate and strong electron-phonon coupling we supplement the SCBA, describing the string of phonons left behind by the carrier, with the Momentum Average (MA) approximation to describe the phonon cloud that accompanies the resulting polaron. We find that coupling to the lattice delocalizes the carrier, as expected, although long-lived resonances resulting from the Wannier-Stark states of the polaron may appear in the spectrum in certain regions of the parameter space. The approach we propose here can also be used to implement and check the validity of simple variational approximations.

References in corpus (14)

• Polymer-Fullerene Bulk Heterojunction Solar Cells
• Wannier-Stark resonances in optical and semiconductor superlattices
• The Holstein Polaron
• Green's function of a dressed particle
• Sharp transition for single polarons in the one-dimensional Su-Schrieffer-Heeger model
• The Green's Function of the Holstein Polaron
• Single-Crystal Organic Charge-Transfer Interfaces probed using Schottky-Gated Heterostructures
• Nonequilibrium dynamics of the Holstein polaron driven by external electric field
• Systematic improvement of the Momentum Average approximation for the Green's function of a Holstein polaron
• Inelastic Quantum Transport
• Investigating polaron transitions with polar molecules
• Momentum average approximation for models with electron-phonon coupling dependent on the phonon momentum
• Holstein polarons in a strong electric field: delocalized and stretched states
• Delocalization of Wannier-Stark ladders by phonons: tunneling and stretched polarons

Cited by in corpus (5)

• Real-time decay of a highly excited charge carrier in the one-dimensional Holstein model
• Transient dynamics of a one-dimensional Holstein polaron under the influence of an external electric field
• Dynamical control of electron-phonon interactions with high-frequency light
• Drift of Charge Carriers in Crystalline Organic Semiconductors
• Keldysh field theory of a driven dissipative Mott insulator: nonequilibrium response and phase transitions