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Updated: Mar 16, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Phonon-Enabled Carrier Transport of Localized States at Non-Polar Semiconductor Surfaces: A First-Principles-Based
Dong Han1,2,3, Junhyeok Bang4, Weiyu Xie1
1Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute , Troy, New York 12180, United States.
Abstract:
Electron-phonon coupling can hamper carrier transport either by scattering or by the formation of mass-enhanced polarons. Here, we use time-dependent density functional theory-molecular dynamics simulations to show that phonons can also promote the transport of excited carriers. Using nonpolar InAs (110) surface as an example, we identify phonon-mediated coupling between electronic states close in energy as the origin for the enhanced transport. In particular, the coupling causes localized excitons in the resonant surface states to propagate into bulk with velocities as high as 10(6) cm/s. The theory also predicts temperature enhanced carrier transport, which may be observable in ultrathin nanostructures.
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