Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nondiffusive thermal transport from micro/nanoscale sources producing
  nonthermal phonon populations exceeds Fourier heat conduction   We study nondiffusive thermal transport by phonons at small distances within
the framework of the Boltzmann transport equation (BTE) and demonstrate that
the transport is significantly affected by the distribution of phonons emitted
by the source. We discuss analytical solutions of the steady-state BTE for a
source with a sinusoidal spatial profile, as well as for a three- dimensional
Gaussian hot spot, and provide numerical results for single crystal silicon at
room temperature. If a micro/nanoscale heat source produces a thermal phonon
distribution, it gets hotter than predicted by the heat diffusion equation;
however, if the source predominantly produces low-frequency acoustic phonons
with long mean free paths, it may get significantly cooler than predicted by
the heat equation, yielding an enhanced heat transport.

13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
24
The categories of this paper are: dg-ga