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arXiv · 2401.15283

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

Wenjiang Zhou·Te-Huan Liu·Bai Song
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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 $^3\rm{H}$ is replaced with $^1\rm{H}$. 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.

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Wenjiang Zhou, Te-Huan Liu, Bai Song. 2024-01-27. Isotope engineering of carrier mobility via Fr\"ohlich electron-phonon interaction. https://doi.org/10.1103/physrevb.109.l121201

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