[8p-Z09-1~18] 22.1 Joint Session M "Phonon Engineering"

▲ [8p-Z09-7] Probing Ballistic Thermal Transport Driven by Surface Phonon Polaritons in Dielectric Nanofilms

〇(P)Yunhui WU¹, Jose ORDONEZ-MIRANDA², Laurent JALABERT^1,3, Saeko TACHIKAWA¹, Roman ANUFRIEV¹, Sebastian VOLZ^1,3, Masahiro NOMURA¹ (1.IIS-Tokyo Univ., 2.Pprime Inst. France, 3.LIMMS-CNRS/IIS-Tokyo Univ.)

Keywords:thin film, surface phonon-polaritons, ballistic thermal conduction

Ballistic heat transport involving thermal conduction without heating up the system, has attracted great attention due to its potential applications for improving the thermal performance in nanoelectronics. However, ballistic heat transport was so far observed only due to non-diffusive heat conduction by phonons. As novel heat carriers, surface phonon polaritons (SPhPs) generated by the hybridation of optical phonons and photons, can ballistically propagate typical distances of a few hundred micrometers. In this work, we conduct 3ω measurements on suspended SiN nanofilms to investigate the ballistic transport driven by SPhPs. Our results confirm that the SPhPs heat contribution has strong dependence on the propagation lengths and show only up for very thin nanofilms, as established by theory. The obtained results can thus have potential applications in thermal management, near-field radiation, and polaritonics.