Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stability of nodal quasi-particles in superconductors with coexisting
  orders   We establish a condition for the perturbative stability of zero energy nodal
points in the quasi-particle spectrum of superconductors in the presence of
coexisting \textit{commensurate} orders. The nodes are found to be stable if
the Hamiltonian is invariant under time reversal followed by a lattice
translation. The principle is demonstrated with a few examples. Some
experimental implications of various types of assumed order are discussed in
the context of the cuprate superconductors.

30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
23
The categories of this paper are: solv-int