Ali Passian - Knoxville TN,
Laurene Tetard - Knoxville TN,
Thomas George Thundat - Knoxville TN,
Brian Henry Davison - Knoxville TN,
Martin Keller - Knoxville TN,
A method for determining chemical characteristics of a sample, the method including directly applying a first acoustic wave at a first frequency to a probe and applying, independent of the directly applying the first acoustic wave, a second acoustic wave at a second frequency to the sample, wherein the first frequency is different than the second frequency and the first acoustic wave and the second acoustic wave are simultaneously applied to the probe and the sample, respectively, and form a coupling. The method further including applying electromagnetic energy to the sample, wherein the electromagnetic energy is absorbed by the sample causing a change in phase of the second acoustic wave. The method further including detecting an effect of the coupling and determining a spectrum of the sample based on the detecting.