Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hybridization gap and anisotropic far-infrared optical conductivity of
  URu2Si2   We performed far-infrared optical spectroscopy measurements on the heavy
fermion compound URu 2 Si 2 as a function of temperature. The light's
electric-field was applied along the a-axis or the c-axis of the tetragonal
structure. We show that in addition to a pronounced anisotropy, the optical
conductivity exhibits for both axis a partial suppression of spectral weight
around 12 meV and below 30 K. We attribute these observations to a change in
the bandstructure below 30 K. However, since these changes have no noticeable
impact on the entropy nor on the DC transport properties, we suggest that this
is a crossover phenomenon rather than a thermodynamic phase transition.

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The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
13
The categories of this paper are: quant-ph
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph