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arXiv · 0805.0405

Enhancement of the superconducting transition temperature in La2-xSrxCuO4 bilayers: Role of pairing and phase stiffness

Ofer Yuli·Itay Asulin·Leonid Iomin·Gad Koren·Oded Millo·Dror Orgad
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Abstract

The superconducting transition temperature, Tc, of bilayers comprising underdoped La2-xSrxCuO4 films capped by a thin heavily overdoped metallic La1.65Sr0.35CuO4 layer, is found to increase with respect to Tc of the bare underdoped films. The highest Tc is achieved for x = 0.12, close to the 'anomalous' 1/8 doping level, and exceeds that of the optimally-doped bare film. Our data suggest that the enhanced superconductivity is confined to the interface between the layers. We attribute the effect to a combination of the high pairing scale in the underdoped layer with an enhanced phase stiffness induced by the overdoped film.

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Ofer Yuli, Itay Asulin, Leonid Iomin, Gad Koren, Oded Millo, Dror Orgad. 2008-08-12. Enhancement of the superconducting transition temperature in La2-xSrxCuO4 bilayers: Role of pairing and phase stiffness. https://doi.org/10.1103/physrevlett.101.057005

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