Superconducting properties of La-substituted Bi-2201 crystals

Ya. G. Ponomarev; N. Z. Timergaleev; Kim Ki Uk; M. A. Lorenz; G. Mueller; H. Piel; H. Schmidt; A. Krapf; T. E. Os'kina; Yu. D. Tretyakov; V. F. Kozlovskii

arXiv · cond-mat/0111340

Superconducting properties of La-substituted Bi-2201 crystals

Ya. G. Ponomarev·N. Z. Timergaleev·Kim Ki Uk·M. A. Lorenz·G. Mueller·H. Piel·H. Schmidt·A. Krapf·T. E. Os'kina·Yu. D. Tretyakov·V. F. Kozlovskii

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Abstract

The superconducting gap Delta has been measured in Bi2Sr2-xLaxCuO6+d single crystals in a wide range of temperatures 4.2 K < T < Tc by point-contact and tunnelling spectroscopy for current in c-direction. The value of Delta(4.2 K) was found to scale with the critical temperature Tc in the whole range of doping levels with the ratio 2D/kTc = 12.5 +/- 2. The closing of the gap Ds at T = Tc has been registered in the underdoped, optimally doped as well as in the overdoped sam-ples.

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Ya. G. Ponomarev, N. Z. Timergaleev, Kim Ki Uk, M. A. Lorenz, G. Mueller, H. Piel, H. Schmidt, A. Krapf, T. E. Os'kina, Yu. D. Tretyakov, V. F. Kozlovskii. 2001-11-19. Superconducting properties of La-substituted Bi-2201 crystals. https://arxiv.org/abs/cond-mat/0111340

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