ZhETF, Vol. 119,
No. 5,
p. 987 (May 2001)
(English translation - JETP,
Vol. 92, No. 5,
p. 858,
May 2001
available online at www.springer.com
)
THE INSTABILITY POINT Hs OF THE MEISSNER STATE FOR LARGE-\kappa SUPERCONDUCTORS
Ovchinnikov Yu.N.
Received: January 2, 2001
PACS: 74.40.+k
The critical field Hs corresponding to the emergence of vortices in a superconductor without a threshold is found near the transition temperature and in limit as for an arbitrary value of the depairing factor Γ. In superconductors of the second kind, this field value coincides with the absolute instability point of the Meissner state. In large-κ superconductors, the order parameter tends to zero on the surface of the superconductor if the external magnetic field reaches the value Hs. We obtain that Hs=Hcm (where Hcm is the thermodynamic critical field) for an arbitrary value of the depairing factor Γ in the temperature region near Tc and at T=0.
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