Noncontact photoacoustic measurements of semiconductors with Michelson interferometry

Noncontact photoacoustic measurements were performed on GaAs samples with Michelson interferometry. The detection sensitivity of the vibration amplitude up to 0.01 Å was achieved. It is demonstrated that the sensitivity is increased drastically by the resonance of the sample itself. The sensitivity for the temperature rise is estimated to be on the order of 2×10−5 °C.