The aim of this work is to provide an analytical expression for the thermal diffusivity of a material in the configuration of the picosecond photoreflectance experiment. It is shown that the thermal diffusivity can be estimated from the absorption depth of the pump beam together with the probe beam as well as the time when the two asymptotic behaviors of the impulse response cross. Thereby, it is not required to measure absolute values of incident heat flux and average temperature on the aiming area.
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.Copyright © 2007
by American Society of Mechanical Engineers
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