2017/05/25 by Anna N. Morozovska, Eugene А. Eliseev, Morozovska, Anna N. +10
Engineering · #Thermography and Photoacoustic Techniques #Thermal Radiation and Cooling Technologies #Photoacoustic and Ultrasonic Imaging
paper · pdf · doi:10.48550/arxiv.1705.09341
The contrast formation mechanism in Nanoscale Infrared Spectroscopy (Nano-IR\nor AFM-IR) is analyzed for the boundary between two layers with different light\nabsorption, thermal and elastic parameters. Analytical results derived in the\ndecoupling approximation for low frequency limit show that the response\namplitude is linearly proportional to the intensity of the illuminating light\nand thermal expansion coefficient. The spatial resolution between two\ndissimilar materials is linearly proportional to the sum of inverse light\nadsorption coefficients and to the effective thermal transfer length. The\ndifference of displacements height across the T-shape boundary ("thermo-elastic\nstep") is proportional to the difference of the adsorption coefficients and\ninversely proportional to the heat transfer coefficient. The step height\nbecomes thickness-independent for thick films and proportional to h2 in a very\nthin film\n