title: Charge separation at nanoscale interfaces: energy-level alignment including two-quasiparticle interactions.
abstract: The universal and fundamental criteria for charge separation at interfaces involving nanoscale materials are investigated. In addition to the single-quasiparticle excitation, all the two-quasiparticle effects including exciton binding, Coulomb stabilization, and exciton transfer are considered, which play critical roles on nanoscale interfaces for optoelectronic applications. We propose a scheme allowing adding these two-quasiparticle interactions on top of the single-quasiparticle energy level alignment for determining and illuminating charge separation at nanoscale interfaces. Employing the many-body perturbation theory based on Green's functions, we quantitatively demonstrate that neglecting or simplifying these crucial two-quasiparticle interactions using less accurate methods is likely to predict qualitatively incorrect charge separation behaviors at nanoscale interfaces where quantum confinement dominates.
authors.affiliation: Department of Physics, Colorado School of Mines, Golden, Colorado 80401, USA.
authors.forename: Huashan
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Physics, Colorado School of Mines, Golden, Colorado 80401, USA.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Department of Physics, Colorado School of Mines, Golden, Colorado 80401, USA.
authors.forename: Mark T
authors.initials: MT
authors.lastname: Lusk
authors.affiliation: Department of Physics, Colorado School of Mines, Golden, Colorado 80401, USA.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Wu