Thermophysical property measurements using time-resolved photothermal deflection spectrometry with step optical excitation

Abstract

This letter reports the theoretical and experimental results of thermophysical property measurements using our recently developed time-resolved photothermal deflection spectrometry (PDS) with step optical excitation. One-dimensional heat conduction boundary conditions of the third kind were derived, and a theoretical model with the boundary conditions was proposed. Both thermal diffusivity and effusivity of two well-known samples were precisely measured simultaneously by fitting experimental data to the theory. Thermal conductivity and unit volume specific heat then can be deduced. Moreover, time-resolved PDS with step optical excitation has the advantages of simpler experimental apparatus and less time consuming measurement, compared with the traditional periodically modulated PDS.

Application of complex geometrical optics to determination of thermal, transport, and optical parameters of thin films by the photothermal beam deflection technique

“…The goal of this work is to develop the theoretical description of the photothermal beam deflection [11] phenomenon on thin films for determination of their thermal (thermal diffusivity and conductivity), optical (energy band gap), and transport (carrier life time) properties during a single measurement, including, to our knowledge for the first time in PDS theoretical analysis, the refraction of probe beam (PB) at TO.…”

Characterizing the Thermal Properties of Solid Materials with Weakly Absorption by the Transient Thermal Grating Method

“…Thermophysical properties of materials are very important parameters used in the designing thermal spreader [1,2] . How to characterize the thermophysical properties has become an important subject in the measurement field.…”

“…How to characterize the thermophysical properties has become an important subject in the measurement field. Photoacoustics and photothermal detection method is attractive in this subject because it is versatile, nondestructive, noninvasive and very sensitive [1][2][3][4] . When two coherent laser beams separated from a pulse laser by half splitter overlap together at the surface of the samples, the TTG will be generated and, through absorption, excited thermal displacement at the surface of the sample.…”