Open AccessDirectional thermal channeling: A phenomenon triggered by tight packing of heat sources
Author(s) -
Hossein Honarvar,
Joshua Knobloch,
Travis Frazer,
Begoña Abad Mayor,
Brendan McBennett,
Mahmoud I. Hussein,
Henry C. Kapteyn,
Margaret M. Murnane,
Jorge N. Hernández-Charpak
Publication year - 2021
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2109056118
Subject(s) - phonon , thermal conduction , thermoelectric materials , materials science , nanoelectronics , thermoelectric effect , scattering , thermoelectric cooling , heat sink , nanoscopic scale , condensed matter physics , mean free path , thermal , thermal conductivity , nanotechnology , physics , thermodynamics , optics , composite material
Understanding nanoscale thermal transport is critical for nano-engineered devices such as quantum sensors, thermoelectrics, and nanoelectronics. However, despite overwhelming experimental evidence for nondiffusive heat dissipation from nanoscale heat sources, the underlying mechanisms are still not understood. In this work, we show that for nanoscale heat source spacings that are below the mean free path of the dominant phonons in a substrate, close packing of the heat sources increases in-plane scattering and enhances cross-plane thermal conduction. This leads to directional channeling of thermal transport-a novel phenomenon. By using advanced atomic-level simulations to accurately access the lattice temperature and the phonon scattering and transport properties, we finally explain the counterintuitive experimental observations of enhanced cooling for close-packed heat sources. This represents a distinct fundamental behavior in materials science with far-reaching implications for electronics and future quantum devices.