Phonon hydrodynamics in frequency-domain thermoreflectance experiments

The hydrodynamic heat transport equation with appropriate boundary conditions and ab initio calculated coefficients is validated by comparing the corresponding analytical and numerical solutions with frequency-domain thermoreflectance experimental measurements in silicon. Special attention is devote...

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Detalles Bibliográficos
Autores: Beardo, Albert|||0000-0003-1889-1588, Hennessy, Matthew G.|||0000-0002-5928-6256, Sendra Molins, Lluc|||0000-0001-8821-6831, Camacho, Juan|||0000-0002-8095-4167, Myers, T. G.|||0000-0001-7573-8059, Bafaluy, Javier|||0000-0003-1972-9339, Alvarez, F. Xavier|||0000-0001-6746-2144
Tipo de recurso: artículo
Fecha de publicación:2020
País:España
Institución:Universitat Autònoma de Barcelona
Repositorio:Dipòsit Digital de Documents de la UAB
Idioma:inglés
OAI Identifier:oai:ddd.uab.cat:304147
Acceso en línea:https://ddd.uab.cat/record/304147
https://dx.doi.org/urn:doi:10.1103/PhysRevB.101.075303
Access Level:acceso abierto
Palabra clave:Heat transfer
Nanostructures
Boltzmann theory
Finite-element method
First-principles calculations
Thermoreflectance
Descripción
Sumario:The hydrodynamic heat transport equation with appropriate boundary conditions and ab initio calculated coefficients is validated by comparing the corresponding analytical and numerical solutions with frequency-domain thermoreflectance experimental measurements in silicon. Special attention is devoted to identifying the resistive effects appearing at the interface between the metal transducer and the silicon substrate. We find that a Fourier model using frequency-dependent effective thermal conductivity cannot simultaneously explain the experimental phase shifts and the amplitude of the temperature oscillations, whereas the hydrodynamic model using intrinsic parameters provides good agreement across a wide temperature range. In addition, phenomenology appearing at reduced length and time scales in this kind of experiment at different temperatures is shown. Specifically, we find hydrodynamic modes of thermal transport that are analogous to pressure- and shear-wave propagation in viscoelastic media.