Analysis of ultrasonic echoes induced by pulsed laser action on an iron film in a diamond anvil cell

Abstract

The results of laser ultrasonic experiments with iron film under high pressure are described. In addition to skimming and bulk acoustic modes observed and analyzed in a previous study [1], the detection of “mixed modes” or head waves is reported. For these modes, the acoustic disturbance propagates along a part of its ray trajectory between the excitation and detection point as a skimming wave on the diamond/iron interface and along another part of its ray trajectory as a bulk wave in iron. Experimentally measured arrival times of the head waves were found to be in a good agreement with the theory.