Confined optical phonon modes in polar tetrapod nanocrystals detected by resonant inelastic light scattering

TL;DR

This study explores the vibrational properties of CdTe tetrapod nanocrystals using resonant inelastic light scattering, revealing confined optical phonon modes and their dependence on size and temperature.

Contribution

It provides the first detailed analysis of confined optical phonon modes in polar tetrapod nanocrystals using resonant inelastic light scattering.

Findings

Detection of confined longitudinal-optical phonons

Observation of surface-optical phonons

Resonant behavior linked to excitonic structure

Abstract

We investigated CdTe nanocrystal tetrapods of different sizes by resonant inelastic light scattering at room temperature and under cryogenic conditions. We observe a strongly resonant behavior of the phonon scattering with the excitonic structure of the tetrapods. Under resonant conditions we detect a set of phonon modes that can be understood as confined longitudinal-optical phonons, surface-optical phonons, and transverse-optical phonons in a nanowire picture.