Ginzburg-Landau equation and the upper critical field in anisotropic (d+s)-wave superconductivity

Based on two-band isotropic Ginzburg–Landau theory, we study the temperature dependence of upper critical field and London penetration depth for non-centrosymmetric superconductor LaNiC2. All the theoretical calculations fit the experimental data very well, especially the upward curvature of upper critical field near the critical temperature. Our results thus indicate that the two-gap scenario is better to account for the superconductivity of LaNiC2, and the Cooper pairs of this superconductor are in the conventional s-wave state.

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Ginzburg–Landau Theory for Two-Band Isotropic s-Wave Superconductors

International Journal of Modern Physics B ◽

10.1142/s0217979203015887 ◽

2003 ◽

Vol 17 (16) ◽

pp. 3001-3020 ◽

Cited By ~ 2

Author(s):

I. N. Askerzade

Keyword(s):

Magnetic Field ◽

Critical Field ◽

Landau Theory ◽

Upper Critical Field ◽

Single Band ◽

S Wave ◽

Ginzburg Landau ◽

Surface Magnetic Field ◽

Specific Heat Jump ◽

Gl Theory

Temperature dependence of the upper critical field Hc2(T), lower critical field Hc1(T) and thermodynamic magnetic field Hcm(T) are studied in the vicinity of Tc using a two-band Ginzburg–Landau (GL) theory. The results are shown to be in a good agreement with experimental data for the superconducting magnesium diboride (MgB2) and non-magnetic borocarbides LuNi 2 B 2 C ( YNi 2 B 2 C ). In addition, two-band GL theory was applied for the calculation of specific heat jump, which is smaller than in single-band GL theory. Peculiarities of Little–Parks effect in two-band GL theory are studied also. It is shown that the quantization of the magnetic flux and the relation between surface magnetic field Hc3(T) and upper critical field Hc2(T) are the same as in single band GL theory.

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The Study on Surface Critical Magnetic Field of a Layered Magnetic Superconductors

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.979.224 ◽

2014 ◽

Vol 979 ◽

pp. 224-227 ◽

Cited By ~ 1

Author(s):

Sumitta Meakniti ◽

Arpapong Changjan ◽

Pongkaew Udomsamuthirun

Keyword(s):

Magnetic Field ◽

Magnetic Property ◽

Variational Method ◽

Critical Field ◽

Landau Equation ◽

Critical Magnetic Field ◽

Ginzburg Landau ◽

Ginzburg Landau Equation ◽

Non Linear

In this research, we studied the surface critical magnetic field () of a layered magnetic superconductors by Ginzburg-Landau approach. After the 1st Ginzburg-Landau equation was calculated, a surface critical field was solved by variational method analytically. Our formula obtained was depended on the magnetic property of superconductor. We found that Hc3 of antiferromagnetism and paramagnetism superconductors were shown the same behaviour as non-magnetic superconductors. For diamagnetism and ferromagnetism superconductors, the higher and the lower values of critical magnetic field were found, respectively. However, the Hc3 was strongly depended on the non-linear of magnetic field intend of all kind magnetism.

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