# Phonon sidebands of color centers in hexagonal boron nitride

## TL;DR

This paper analyzes the phonon sidebands in the photoluminescence spectra of color centers in hexagonal boron nitride, revealing detailed coupling mechanisms with acoustic and optical phonons.

## Contribution

It provides a detailed model of phonon coupling in hBN color centers, including deformation and Frohlich interactions, and reports defect-specific phonon resonances.

## Key findings

- Acoustic phonon sideband described by 2D deformation coupling.
- Optical phonon band modeled by Frohlich and deformation couplings.
- Variation in optical resonances and out-of-plane phonon coupling among defects.

## Abstract

Low temperature photoluminescence spectra of a color center in hexagonal boron nitride are analyzed. The acoustic phonon sideband can be described by a deformation coupling proportional to strain to a phonon bath that is effectively two dimensional. The optical phonon band is described by Frohlich coupling to the LO-branches, and a deformation coupling proportional to lattice displacement for the TO-branch. The resonances expressed in the optical band vary from defect to defect, in some emitters, coupling to out-of-plane polarized phonons is reported.