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Register a new userPair-breaking of multi-gap superconductivity under parallel magnetic fields in electric-field-induced surface metallic state
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Roles of paramagnetic and diamagnetic pair-breaking effects in superconductivity in electric-field-induced surface metallic state are studied by Bogoliubov-de Gennes equation, when magnetic fields are applied parallel to the surface. The multi-gap states of sub-bands are related to the depth dependence and the magnetic field dependence of superconductivity. In the Fermi-energy density of states and the spin density, sub-band contributions successively appear from higher-level sub-bands with increasing magnetic fields. The characteristic magnetic field dependence may be a key feature to identify the multi-gap structure of the surface superconductivity.
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We present transport measurements along the least conducting c direction of the organic superconductor (TMTSF)2ClO4, performed under an accurately aligned magnetic field in the low temperature regime. The experimental results reveal a two-dimensional confinement of the carriers in the (a,b) planes which is governed by the magnetic field component along the b direction. This 2-D confinement is accompanied by a metal-insulator transition for the c axis resistivity. These data are supported by a quantum mechanical calculation of the transverse transport taking into account in self consistent treatment the effect of the field on the interplane Green function and on the intraplane scattering time.
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