Phonon-Photon Mapping in a Color Center in Hexagonal Boron Nitride

Phuong Vuong (1) , Guillaume Cassabois (1) , Pierre Valvin (1) , Abdelkarim Ouerghi (2) , Yannick Chassagneux (3) , Christophe Voisin (3) , Bernard Gil (1)

1 L2C - Laboratoire Charles Coulomb
2 LPN - Laboratoire de photonique et de nanostructures
3 LPA - Laboratoire Pierre Aigrain

We report on the ultraviolet optical response of a color center in hexagonal boron nitride. We demonstrate a mapping between the vibronic spectrum of the color center and the phonon dispersion in hexagonal boron nitride, with a striking suppression of the phonon assisted emission signal at the energy of the phonon gap. By means of nonperturbative calculations of the electron-phonon interaction in a strongly anisotropic phonon dispersion, we reach a quantitative interpretation of the acoustic phonon sidebands from cryogenic temperatures up to room temperature. Our analysis provides an original method for estimating the spatial extension of the electronic wave function in a point defect.

Domaines: Autre [cond-mat.other]

Phuong Vuong, Guillaume Cassabois, Pierre Valvin, Abdelkarim Ouerghi, Yannick Chassagneux, et al.. Phonon-Photon Mapping in a Color Center in Hexagonal Boron Nitride. Physical Review Letters, 2016, 117, pp.097402. ⟨10.1103/PhysRevLett.117.097402⟩. ⟨hal-01362938⟩