Laser picosecond acoustics in isotropic and anisotropic materials

We present experimental results concerning the laser generation of picoseco nd acoustic pulses and their propagation in isotropic and anisotropic mater ials. We make use of a conventional reflectance detection technique as well as interferometric detection to probe the real and imaginary changes in re flectance. We also demonstrate the detection of transverse acoustic waves b y mode conversion at an interface between an isotropic polycrystalline film and an anisotropic substrate, (C) 2000 Elsevier Science B.V. All rights re served.