Surface Phonon-Polariton Heat Capacity of Polar Nanofilms

The surface phonon-polariton heat capacity of polar nanofilms is analytically determined and analyzed as a function their thickness temperature. It shown that the polariton increases with square nanofilm thickness, such for thin enough at sufficient low temperature $T$, its value becomes independent material properties given by $C=1.15{\ensuremath{\epsilon}}_{0}{k}_{B}{({k}_{B}T/\ensuremath{\hbar}c)}^{2}$, where ${\ensuremath{\epsilon}}_{0}$ $c$ are respective relative permittivity surrounding medium light speed in vaccum, while ${k}_{B}$ $2\ensuremath{\pi}\ensuremath{\hbar}$ Boltzmann Planck constants, respectively. photonlike nature phonon polaritons found to be responsible main contribution capacity. As result close hence much higher than phonons, ${\mathrm{Si}\mathrm{O}}_{2}$, SiC, $\mathrm{SiN}$ several orders magnitude smaller corresponding counterpart. Surface thus not expected increase expansion coefficient nanofilms, which favors utilization effective dissipators.