Fundamentals of picosecond laser ultrasonics

Osamu Matsuda; Maria Cristina Larciprete; Roberto Li Voti; Oliver B Wright

doi:10.1016/j.ultras.2014.06.005

Fundamentals of picosecond laser ultrasonics

Ultrasonics. 2015 Feb:56:3-20. doi: 10.1016/j.ultras.2014.06.005. Epub 2014 Jun 16.

Authors

Osamu Matsuda¹, Maria Cristina Larciprete², Roberto Li Voti², Oliver B Wright³

Affiliations

¹ Division of Applied Physics, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan. Electronic address: omatsuda@eng.hokudai.ac.jp.
² Dipartimento di Scienze di Base ed Applicate per l'Ingegneria, Sapienza Università di Roma, Via A. Scarpa 14, 00161 Roma, Italy.
³ Division of Applied Physics, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.

PMID: 24998119
DOI: 10.1016/j.ultras.2014.06.005

Abstract

The aim of this article is to provide an introduction to picosecond laser ultrasonics, a means by which gigahertz-terahertz ultrasonic waves can be generated and detected by ultrashort light pulses. This method can be used to characterize materials with nanometer spatial resolution. With reference to key experiments, we first review the theoretical background for normal-incidence optical detection of longitudinal acoustic waves in opaque single-layer isotropic thin films. The theory is extended to handle isotropic multilayer samples, and is again compared to experiment. We then review applications to anisotropic samples, including oblique-incidence optical probing, and treat the generation and detection of shear waves. Solids including metals and semiconductors are mainly discussed, although liquids are briefly mentioned.

Keywords: Gigahertz and terahertz acoustic waves; Green’s function; Interferometer; Longitudinal and shear acoustic waves; Optical pump-probe technique.