Quasi-one-dimensional thermal transport in trigonal selenium crystal

Area of Science:

• Materials Science
• Condensed Matter Physics
• Solid State Chemistry

Background:

• Van der Waals crystal selenium possesses unique thermal transport properties.
• Understanding lattice thermal conductivity is crucial for thermal management in electronic devices.

Purpose of the Study:

• To investigate the lattice thermal conductivity of selenium using first-principles calculations.
• To elucidate the anisotropic heat transfer characteristics in selenium.

Main Methods:

• Solving the phonon Boltzmann transport equation.
• Employing first-principles calculations to model phonon behavior.

Main Results:

• Selenium shows significantly lower thermal conductivity perpendicular to its chains (5x lower than parallel).
• This anisotropy is attributed to low phonon group velocity, acoustic-optical phonon mixing, and anharmonic bonding.
• Nanoscale particles drastically reduce thermal conductivity through boundary scattering.

Conclusions:

• Selenium exhibits quasi-one-dimensional heat transport due to its anisotropic thermal conductivity.
• Its low thermal conductivity and unique transport properties position selenium as a potential material for thermoelectric and electronic thermal management applications.