<\/a>Figure 1: Time-resolved anti-Stokes Raman imaging schematic. A) A high-energy pulsed laser excites and locally heats the sample with a Gaussian excitation profile. B) After a variable delay time \u0394t, the Raman probe laser measures the anti-Stokes scattered signal at a known distance from the excitation source. By varying the position and time between the laser pulses, we will map the thermal properties of our samples.<\/p><\/div>\n
Thermal management in nanoscale materials dramatically affects the efficiency of novel energy generation technologies, and engineering devices with appropriate heat transport properties is requisite for their success. We are using Raman spectroscopy to measure and visualize heat transport in nanostructured materials, such as organic\/polymeric or quantum dot thin films, which may be used for photovoltaic or thermoelectric devices. Raman spectroscopy measures the inelastic scatting of light off a sample, and the resulting spectrum contains a chemical fingerprint of the molecules involved in heat transport as well as a measure of local temperature via vibrational excitations. In particular, through pulsed local heating of a sample and measuring the temperature of a nearby point a known distance and time away with Raman spectroscopy, we can visualize thermal diffusion and unveil the vibrational pathways involved[