First-principles study of the mobility of SrTiO$_3$

TL;DR

This study uses first-principles calculations to analyze the electronic and vibrational properties of SrTiO₃, revealing key factors affecting its room-temperature electron mobility and guiding material engineering for improved performance.

Contribution

It provides a detailed first-principles analysis of electron-phonon interactions and mobility in SrTiO₃, offering new insights into how phonon scattering limits mobility.

Findings

Results agree with experimental mobility measurements.

Longitudinal optical phonons strongly impact mobility.

Insights suggest pathways to enhance material mobility.

Abstract

We investigate the electronic and vibrational spectra of SrTiO$_3$, as well as the coupling between them, using first-principles calculations. We compute electron-phonon scattering rates for the three lowest-energy conduction bands and use Boltzmann transport theory to calculate the room-temperature mobility of SrTiO$_3$. The results agree with experiment and highlight the strong impact of longitudinal optical phonon scattering. Our analysis provides important insights into the key factors that determine room temperature mobility, such as the number of conduction bands and the nature and frequencies of longitudinal phonons. Such insights provide routes to engineering materials with enhanced mobilities.