Characteristics of coherent transverse optical phonon in CuI thin films on Au nano-films*
Department of Physical Science, Osaka Prefecture
2 National Institute of Information and Communications Technology, Japan
Received: 16 July 2012
Received in final form: 18 December 2012
Published online: 22 April 2013
We have investigated the coherent phonon in CuI thin films deposited on Au films with nanoscale roughness. It is found that the coherent transverse optical (TO) phonon in the CuI thin film on the Au film is dramatically enhanced, whereas that in the CuI thin film without the Au film is hardly observed. The enhancement of the coherent TO phonon in the CuI thin film on the Au film will originate from the surface enhanced electric field around the surface of the Au film with nanoscale roughness. To clarify the properties of the enhanced coherent phonon, we have investigated the pump-power dependence and pump-polarization dependence of the coherent phonon. We discuss the generation process of the coherent phonon in the CuI thin film on the Au film as compared with the pump-power dependence and the pump-polarization dependence.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2013