Low-dimensional heat conduction in surface phonon polariton waveguide.

Area of Science:

• Solid-state physics
• Nanophotonics
• Heat transfer

Background:

• Fourier's law governs heat conduction via diffusion of phonons and electrons with short mean free paths.
• Surface phonon polaritons (SPPs) couple thermal photons and optical phonons, exhibiting longer wavelengths and propagation lengths.
• SPPs offer potential for enhanced heat transfer in polar dielectric materials.

Purpose of the Study:

• To investigate and observe heat conduction mediated by SPPs in SiO2 nanoribbons.
• To demonstrate non-Fourier heat transfer behavior at microscale distances.
• To explore the manipulation of heat conduction beyond conventional limits.

Main Methods:

• Fabrication of SiO2 nanoribbon waveguides (20-50 nm thick, 1-10 μm wide).
• Rational design of waveguides to control SPP mode size and coupling to thermal reservoirs.
• Experimental observation of thermal conductivity and non-Fourier heat transfer phenomena.

Main Results:

• Clear observation of thermal conductivity mediated by SPPs in SiO2 nanoribbons.
• Demonstration of non-Fourier heat transfer behavior over distances of 50-100 μm.
• Successful control over SPP mode size and thermal coupling.

Conclusions:

• SPPs can mediate extraordinary heat transfer in solids, exceeding traditional diffusion limits.
• Non-Fourier heat transfer is achievable via SPPs at microscale.
• This work provides a foundation for manipulating heat conduction using SPP waves.