3:45 PM - 4:00 PM
▲ [22p-C102-9] Resonant Polariton Thermal Transport along a Vacuum Gap
Keywords:Surface phonon-polaritons, Heat transport along a cavity, Super-Planckian heat transport
Surface Phonon-Polaritons (SPhPs) are electromagnetic surface modes generated by the coupling of infrared photons with optical phonons at the interface of polar materials (i.e., SiO2, SiC, SiN). These surface excitations can significantly enhance the heat transport along polar dielectric nanofilms and across nanoscale cavities. However, to date, the SPhP contribution to the in-plane heat transport along macroscale cavities is not explored yet, despite of the fact that they are powerful energy carriers with huge propagation distances (≥1 mm).
In this work, we theoretically demonstrate the resonant behavior of the in-plane SPhP thermal conductance of a vacuum gap, as a function of its thickness d. In contrast to the well-known cross-plane thermal conductance, we show that the in-plane one exhibits its lowest values as d goes to zero and its highest one at approximately d = 1 cm. This thermal maximization appears due to the thermal activation of hundreds of planar cavity modes, which are propagative in the in-plane direction and standing waves in the cross-plane one. This top polariton thermal conductance along a macroscale cavity increases with temperature and is pretty much equal to the radiative one predicted by Planck's law, which is expected to facilitate its observation and application to amplify or evacuate heat currents. Our original work thus uncovers a SPhP heat transport channel of practical interest along a macroscale cavity.
In this work, we theoretically demonstrate the resonant behavior of the in-plane SPhP thermal conductance of a vacuum gap, as a function of its thickness d. In contrast to the well-known cross-plane thermal conductance, we show that the in-plane one exhibits its lowest values as d goes to zero and its highest one at approximately d = 1 cm. This thermal maximization appears due to the thermal activation of hundreds of planar cavity modes, which are propagative in the in-plane direction and standing waves in the cross-plane one. This top polariton thermal conductance along a macroscale cavity increases with temperature and is pretty much equal to the radiative one predicted by Planck's law, which is expected to facilitate its observation and application to amplify or evacuate heat currents. Our original work thus uncovers a SPhP heat transport channel of practical interest along a macroscale cavity.