Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High-resolution ac-calorimetry studies of the quasi-2D organic
  superconductor $\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$   We report high-resolution specific heat measurements on the quasi-2D organic
superconductor $\kappa$-(BEDT-TTF)$_2$Cu(NCS)$_2$, performed by using a most
sensitive ac-modulation technique. The main observations are (i) a
discontinuity at \tc\ much in excess of what is expected for a weak-coupling
BCS superconductor and (ii) a quasiparticle contribution to the specific heat
with an exponentially weak temperature dependence at $T \ll T_c$. The latter
finding is incompatible with an order parameter that vanishes at certain parts
of the Fermi surface. The data for $T \leq T_c$ can be well described by a
strong-coupling extension of the BCS theory - the $\alpha$-model - similar to
what has been recently found for the $\kappa$-(BEDT-TTF)$_2$Cu[N(CN)$_2$]Br
salt [Elsinger {\em et al.}, Phys. Rev. Lett. {\bf 84}, 6098 (2000)].

26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
18
The categories of this paper are: econ
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
19
The categories of this paper are: eess