Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Reciprocity theorem in high-temperature superconductors   This article is devoted to the problem of the validity of the reciprocity
theorem in high-temperature superconductors (HTSC). The violation of the
reciprocity theorem in zero external magnetic fields has been studied.
Experimental data obtained for two different superconducting materials:
BiSrCaCuO and YBaCuO are presented. Results show that the basic form of the
reciprocity theorem (without consideration of any additional anisotropy) is not
valid near the critical temperature. We assume that the reciprocity theorem
breaking is connected with the existence of an extraordinary transverse
electric field originated from additional anisotropy and more general form of
the reciprocity relations should be valid. However, the origin of this
anisotropy is not clear yet. We suggest that the vortex-antivortex dynamics
model taking into account vortex guiding can be responsible for the observed
effect. Also the explanation based on weak P and T symmetry breaking in HTSC
which is supported by the observation of the spontaneous magnetisation can not
be excluded.

11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
7
The categories of this paper are: hep-th