Absorption cross section and interfacial thermal conductance from an individual optically excited single-walled carbon nanotube

摘要

The heat generation and dissipation of an individual optically excited metallic single-walled carbon nanotube is characterized using a thermal sensor thin film of Al_(0.94)Ga_(0.06)N embedded with Er~(3+). The absorption cross section from an individual SWCNT excited at 532 nm is revealed from the steady-state temperature of the thermal sensor film. A maximum temperature of 4.3 K is observed when the SWCNT is excited with parallel polarization and an average intensity of 7 × 10~(10) W/m ~2. From this temperature measurement, we determine an absorption cross section for the SWCNT of 9.4 × 10~(-17) m~2/μm using parallel polarization and 2.4 × 10~(-17) m~2/μm for perpendicular polarization. We establish a temperature difference between the SWCNT and the substrate of 315 K by converting the G band shift of the SWCNT into the local SWCNT temperature and scaling the measured film temperature to the local non-resolution-limited temperature rise. From the temperature difference and heat flux, we deduce a value of 6.6 MW/m~2~·K for the thermal interfacial conductance of a SWCNT sitting on a thin film of amorphous Al_(0.94)Ga_(0.06)N.