Elasticity of ultrathin copper-phthalocyanine Langmuir-Blodgett films by picosecond ultrasonics

Abstract

The elastic properties of nanometric CuC4Pc Langmuir-Blodgett films were investigated using the picosecond ultrasonics technique (PUT). PUT is based on the estimation of longitudinal sound velocity and ultrasonic attenuation in the films from the behavior of the photoelastic response against the number of individual layers. It is independent on the optical properties or on the chemical nature of the compound and applies to any material that can be deposited on a metallic surface. As the method is mass-sensitive, the precise knowledge of the density of the material limits its accuracy.