Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Static and Dynamical Anisotropy Effects in Mixed State of D - Wave
  Superconductors   We describe effects of anisotropy caused by the crystal lattice in d-wave
superconductors with s-wave mixing using the effective free energy approach.
Only the d-wave order parameter field $d$ is introduced, while the effect of
the s wave mixing as well as other effects breaking the rotational symmetry
down to the fourfold symmetry of the crystal are represented by a single four
(covariant) derivative term: $\eta d^{*}(\Pi _{y}^{2}-\Pi_{x}^{2})^{2}d $. The
single vortex solution in a phenomenologically interesting range of parameters
is almost identical to the two order parameters approach. We analytically
consider the most general oblique lattice and orientation, but find that only
rectangular body centered lattices are realized. A critical value $\eta _{c} $
at which a phase transition from the rectangular lattice to the square lattice
takes place. The influence on the phase transition line is discussed. The
formalism is extended to the time dependent anisotropic Ginzburg-Landau
equations in order to calculate the effect of the anisotropy on the flux flow.
The moving vortex structure is established and the magnetization as function of
the current is calculated. Although the linear conductivity tensor is
rotationally invariant due to the fourfold symmetry, the nonlinear one shows
anisotropy. We calculate dependence of both direct and Hall I-V curves on the
angle between the current and the crystal lattice orientation.

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The categories of this paper are: funct-an
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The categories of this paper are: solv-int
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The categories of this paper are: stat
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The categories of this paper are: hep-th
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The categories of this paper are: physics
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The categories of this paper are: cs
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The categories of this paper are: econ
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The categories of this paper are: hep-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
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The categories of this paper are: eess
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The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: ao-sci
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The categories of this paper are: gr-qc