Plasmon-Phonon Hybridization in Doped Semiconductors from First Principles

TL;DR

This paper presents a first-principles study of the nonadiabatic hybridization between plasmons and phonons in doped semiconductors, providing a theoretical framework that aligns well with existing Raman data and suggests further experimental validation.

Contribution

The authors develop a novel approach transforming the Dyson equation into a frequency-independent dynamical matrix to study plasmon-phonon hybridization from first principles.

Findings

Good agreement with Raman data for doped GaAs and TiO2.

Framework applicable to various spectroscopic techniques.

Highlights the importance of nonadiabatic effects in doped semiconductors.

Abstract

Although plasmons and phonons are the collective excitations that govern the low-energy physics of doped semiconductors, their nonadiabatic hybridization and mutual screening have not been studied from first principles. We achieve this goal by transforming the Dyson equation to the frequency-independent dynamical matrix of an equivalent damped oscillator. Calculations on doped GaAs and TiO2 agree well with available Raman data and await immediate experimental confirmation from infrared, neutron, electron-energy-loss, and angle-resolved photoemission spectroscopies.