Identification of surface optical phonon in wurtzite InN epitaxial thin films by coherent phonon spectroscopy
Journal
Applied Physics Letters
Journal Volume
90
Journal Issue
7
Pages
072110-1 - 072110-3
Date Issued
2007
Author(s)
Abstract
Coherent phonon spectroscopy of wurtzite InN epitaxial thin films was carried out with time-resolved second-harmonic generation technique. In addition to the bulk A1(LO) phonon and A1(LO)–plasmon coupling modes, a phonon mode at 543cm−1 was identified and characterized. It is found that this phonon mode is localized in the topmost few atomic layers and sensitive to surface modification. This vibration mode is described as the opposite motion between the In and N atoms along the c axis. This phonon mode is assigned to the surface optical phonon of InN.
Publisher
American Institute of Physics
Type
journal article