Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of inhomogeneities and substrate on the dynamics of the
  metal-insulator transition in VO$_2$ thin films   We study the thermal relaxation dynamics of VO$_2$ films after the ultrafast
photo-induced metal-insulator transition for two VO$_2$ film samples grown on
Al$_2$O$_3$ and TiO$_2$ substrates. We find two orders of magnitude difference
in the recovery time (a few ns for the VO$_2$/Al$_2$O$_3$ sample vs. hundreds
of ns for the VO$_2$/TiO$_2$ sample). We present a theoretical model that
accurately describes the MIT thermal properties and interpret the experimental
measurements. We obtain quantitative results that show how the microstructure
of the VO$_2$ film and the thermal conductivity of the interface between the
VO$_2$ film and the substrate affect long time-scale recovery dynamics. We also
obtain a simple analytic relationship between the recovery time-scale and some
of the film parameters.

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The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
13
The categories of this paper are: quant-ph
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The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
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The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg