Contribution of interband effects caused by long-wavelength transverse optical phonons to electron-phonon coupling in doped polar insulators

TL;DR

This paper investigates the role of long-wavelength transverse optical phonons in electron-phonon coupling within doped polar insulators, finding their contribution to be minimal despite initial expectations.

Contribution

It provides analytical and numerical analysis showing that el-TO-ph interactions have limited impact on electron pairing in materials like SrTiO3 and PbTe.

Findings

el-TO-ph interaction contributes little to electron-phonon coupling

The effect of polar TO phonons on the coupling constant lambda is minimal

Analytical and numerical results support the limited role of these phonons

Abstract

We estimate the contribution of the long-wavelength el-TO-ph interaction and discuss the effect it has on electron pairing in doped polar systems like SrTiO3 and PbTe. The analytical and numerical results presented in the study indicate that the el-TO-ph interaction tends to contribute little to the total strength of electron-phonon coupling in these and related materials. To explain this fact we consider possible reasons why the effect of the polar long-wavelength transverse optical phonons on the coupling constant "lambda" is far less than one might suppose.