material design

Cross-plane thermal conductivity in amorphous Si/SiO2 superlattices

Here, we experimentally demonstrate thermal transport in amorphous atomic-scale superlattices that can provide lower thermal conductivity value than amorphous limit.


Investigating phonon transport in phononic crystals, nanowires, and membranes.

Thermal SPhPs

Investigation of thermally excited surface phonon polaritons in nanostructured polar dielectric materials.

Thermal conductivity reduction in a silicon thin film with nanocones

We propose a cost-effective, large-area, and maskless nanofabrication method that creates external nanocones on the silicon surface while preserving its interior. Our experiments show that these nanocones reduce the thermal conductivity of thin silicon membranes by more than 40%.

Probing ballistic thermal conduction in segmented silicon nanowires

Here, we experimentally probed ballistic thermal transport at distances of 400–800 nm and temperatures of 4–250 K. Measuring thermal properties of straight and serpentine silicon nanowires, we found that at 4 K heat conduction is quasi-ballistic with stronger ballisticity at shorter length scales.

On the reduction and rectification of thermal conduction using phononic crystals with pacman-shaped holes

We measure the thermal conductivity of silicon phononic crystals with asymmetric holes at room and liquid helium temperatures and study the effect of thermal rectification, phonon boundary scattering, neck transmission, and hole positioning.

Quasi-ballistic heat conduction due to Lévy phonon flights in silicon nanowires

Here, we experimentally demonstrate quasi-ballistic heat conduction in silicon nanowires (NWs). We show that the ballisticity is the strongest in short NWs at low temperatures but weakens as the NW length or temperature is increased.

Thermal energy manipulation via electromagnetic surface waves at micro and nanoscales

My phd work covers various types of thermal energy manipulation using surface effects at nanoscale and includes theoretical analysis, numerical simulations, nanofabrications, and optical measurements.

Thermal excitation of broadband and long-range surface waves on SiO2 submicron films

We detect thermally excited surfaces waves on a submicron SiO2 layer, including Zenneck and guided modes in addition to Surface Phonon Polaritons. We demonstrate a source of broadband coherent thermal emission by using nanostructured interfaces.

Energy transport of surface phonon polaritons propagating along a chain of spheroidal nanoparticles

We analyze the energy transport of surface phonon polaritons propagating in a chain of spheroidal polar nanoparticles. We develop a theoretical model to quantify the energy transport of SPhPs propagating along these nanostructures.