BTE-Barna: An extension of almaBTE for thermal simulation of devices based on 2D materials

TL;DR

BTE-Barna is a software extension that improves thermal simulations of 2D material-based nanosystems by solving the full phonon Boltzmann transport equation beyond the relaxation-time approximation.

Contribution

It extends almaBTE's Monte Carlo solver to handle complex geometries and full linearized PBTE, enabling detailed thermal analysis of 2D material devices.

Findings

Accurately models phonon transport in nanosystems with complex geometries.

Provides temperature and heat flux distributions under various thermal conditions.

Includes approximations for symmetric device configurations.

Abstract

We present BTE-Barna (Boltzmann Transport Equation - Beyond the Rta for NAnosystems), a software package that extends the Monte Carlo (MC) module of the almaBTE solver of the Peierls-Boltzmann transport equation for phonons (PBTE) to work with nanosystems based on 2D materials with complex geometries. To properly capture how the phonon occupations evolve in momentum space as a result of scattering, we have supplemented the relaxation-time approximation with an implementation of the propagator for the full linearized version of the PBTE. The code can now find solutions for finite and extended devices under the effect of a thermal gradient, with isothermal reservoirs or with an arbitrary initial temperature distribution in space and time, writing out the temperature and heat flux distributions as well as their spectral decompositions. Besides the full deviational MC solver, a number of useful approximations for highly symmetric devices are also included.