Nanoscale transport of phonons: Dimensionality, subdiffusion, molecular damping, and interference effects
- Aerospace Systems Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base, Ohio 45433 (United States)
We examine heat transport carried by acoustic phonons in the systems composed of nanoscale chains of masses coupled to two thermal baths of different temperatures. Thermal conductance is obtained by using linearized Landauer-type formula for heat flux with phonon transmission probability calculated within atomistic Green's functions (AGF) method. AGF formalism is extended onto dissipative chains of masses with harmonic coupling beyond nearest-neighbor approximation, while atomistic description of heat reservoirs is also included into computational scheme. In particular, the phonon lifetimes and the phonon frequency shifts are discussed for harmonic lattices of different dimensions. Further, resonant structure of phonon transmission spectrum is analyzed with respect to reservoir-induced effects, molecular damping, and mass-to-mass harmonic coupling. Analysis of transmission zeros (antiresonances) and their accompanied Fano-shape resonances are discussed as a result of interference effects between different vibrational modes. Finally, we also predict subdiffusive transport regime for low-frequency ballistic phonons propagated along a linear chain of harmonically coupled masses.
- OSTI ID:
- 22280445
- Journal Information:
- Journal of Applied Physics, Vol. 115, Issue 17; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Phonon Transport at the Interfaces of Vertically Stacked Graphene and Hexagonal Boron Nitride Heterostructures
Ballistic spin-dependent transport of Rashba rings with multi-leads