Expertise: Non-equilibrium thermodynamics, kinetic theory and Boltzmann transport, molecular dynamics, light-matter interaction, thermoelectricity, thermoelasticity.

Short bio: I received a Ph.D. in theoretical physics from the Universitat Autònoma de Barcelona (UAB) in 2021. Then, I joined the Kapteyn-Murnane research group in the Department of Physics of the University of Colorado Boulder as a Postdoctoral Associate for three years. In 2024, I became an assistant professor and member of the Department of Physics of the UAB.

Title of Presentation：

Phonon hydrodynamics: Unified modeling from silicon to graphite

Please choose one Forum Theme：

Thermal Management for Chips and Devices

Non-Equilibrium Thermal Transport / Thermophysical Properties under Extreme Conditions

Abstract:

We introduce a theoretical framework for non-Fourier heat transport based on a hydrodynamic expansion of the Boltzmann transport equation that consistently explains a wide range of experimental observations, spanning materials from silicon to graphite and temperatures from cryogenic to room temperature. This approach yields generalized boundary conditions that seamlessly bridge regimes dominated by collective phonon dynamics and those governed by resistive scattering. The framework reveals that phenomena traditionally treated as distinct—such as the apparent reduction of thermal conductivity in nanostructured silicon, the emergence of Poiseuille heat flow in graphite ribbons, or second sound propagation—can be predicted within a unified description.

We reconcile continuum-scale descriptions, including the Guyer–Krumhansl equation, with microscopic approaches based on direct solutions of the Boltzmann transport equation beyond the relaxation-time approximation. This perspective challenges widely held assumptions in nanoscale heat transport, notably the notions of phonon suppression and quasi-ballistic conduction, and provides a coherent interpretation of experimental data that has previously required disparate explanations

Furthermore, the simplicity of the proposed framework enables quantitative modeling of otherwise intractable experiments in low-dimensional materials, including thermoelastic effects on heat transfer in the presence of inhomogeneous strain fields, without resorting to ad hoc assumptions or fitting parameters.