Using Matlab Simulations to Study Heat Flow in Thin Films
Emma Manzella ’21 and Professor Brian Daly (Physics)
We used Matlab to simulate experiments in which a thin metal film of known material properties is grown on top of a thin sample layer and an ultrafast laser pump-probe method is used to heat and measure the thermal conductivity of the sample layer. We became familiar with a Matlab program published by researchers at The University of Illinois that simulated the experiment and used this simulation to determine the ideal experimental parameters for measuring thermal conductivity of MoSe2 and other novel materials that are of interest for nanoscale electronic and optoelectronic devices. A subset of the thermal conductivity simulation allows for testing the sensitivity of material parameters of the metal film, sample layer, and the substrate. We tested the sensitivity of the parameters at different laser modulation frequencies and pump and probe laser spot sizes. The sensitivity simulations allowed us to design the ideal experimental set up in order to optimize the experiment for measuring the thermal conductivity of the sample layer. For MoSe2, we have found that the ideal experimental set up is 1 m MoSe2 with 80 nm Al film, pump and probe spot size radius of 5 um, and 2.0 MHz modulation frequency. We have also designed other experimental set ups for samples <1 m of MoSe2.