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Superconductivity: between "one" and "two"

posted Jan 9, 2010, 9:05 AM by Igor Lukyanchuk   [ updated Oct 19, 2017, 3:45 PM ]

Publications:

Interaction of vortices in superconductors with kappa close to 1/sqrt(2)
F. Mohamed, M. Troyer, G. Blatter, and I. Luk'yanchuk; Phys. Rev. B 65, 224504 (2002)

Theory of superconductors with kappa close to 1/sqrt(2)

As was first shown by Bogomolnyi, the critical Ginzburg-Landau (GL) parameter k5kappa=1/sqrt2 at which a superconductor changes its behavior from type I to type II, is the special highly degenerate point where Abrikosov vortices do not interact and therefore all vortex states have the same energy. Developing a secular perturbation theory, we studied how this degeneracy is lifted when k is slightly different from 1/sqrt2 or when the GL theory is extended to the higher terms in T2Tc . We constructed a simple secular functional that depends only on few experimentally measurable phenomenological parameters and therefore is quite efficient to study the vortex state of superconductor in this transitional region of k . On this base, we calculated such vortex state properties as critical fields, energy of the normal-superconductor interface, energy of the vortex lattice, vortex interaction energy, etc., and compared them with previous results that were based on bulky
solutions of GL equations.


Fullerenes, Magnetic Resonance

posted Jan 9, 2010, 8:53 AM by Igor Lukyanchuk   [ updated Nov 23, 2010, 2:54 PM by Igor Lukyanchuk ]


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