English

Isotope engineering of carrier mobility via Fr\"ohlich electron-phonon interaction

Materials Science 2025-01-22 v1 Applied Physics

Abstract

Isotope effects on phonon properties and transport have been predicted and observed for decades. However, despite the crucial impact of electron-phonon interactions, the effect of isotopes on electron transport remains largely unexplored. Here, by using first-principles calculations, we theoretically predict that the electron mobility of lithium hydride (LiH) can increase by up to ~100% as 3H^3\rm{H} is replaced with 1H^1\rm{H}. This remarkable phenomenon is primarily attributed to the isotope engineering of the Fr\"ohlich interaction by the mass-induced line shift of the longitudinal optical (LO) phonons. Notably, the isotope-dependent absorption of LO phonons dominates while the isotope-insensitive emission process is mostly suppressed due to energy conservation. We further propose general guidelines for evaluating isotope effects on carrier transport in different materials.

Keywords

Cite

@article{arxiv.2401.15283,
  title  = {Isotope engineering of carrier mobility via Fr\"ohlich electron-phonon interaction},
  author = {Wenjiang Zhou and Te-Huan Liu and Bai Song},
  journal= {arXiv preprint arXiv:2401.15283},
  year   = {2025}
}