Andreev reflection on the Ag−BaPb1−xBi x O3 microconstriction: Temperature and magnetic field dependence
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Abstract
The point-contact spectroscopy has been performed on the normal metal-superconductor microconstriction Ag−BaPb1−xBixO3. The conductance curves of our junctions reveal almost ideal Andreev reflection behavior described by theBlonder-Tinkham-Klapwijk theory, with the in-gap conductance twice higher than the conductance at higher voltages. We studied the effect of the temperature and magnetic field on the Andreev reflection. The temperature dependence of the energy gap (determined from the BTK theory) follows the BCS prediction. The value of the reduced gap yields a weak coupling strength in BaPb1−xBixO3. ¿From magnetic measurements up to 10 Tesla the temperature dependence of the upper critical field Hc2 has been determined and found to follow the Werthamer-Helfand-Hohenberg prediction.
PACS numbers
74.50 74.60ePreview
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References
- 1.G.E. Blonder, M. Tinkham and T.M. Klapwijk,Phys. Rev. B 25, 4515 (1995).ADSCrossRefGoogle Scholar
- 2.A. Plecenik et al.,Phys. Rev. B 49, 10016 (1996).ADSCrossRefGoogle Scholar
- 3.H. v. Löhneysen,Physica B 218, 148 (1996).ADSCrossRefGoogle Scholar
- 4.R.C. Dynes et al.,Phys. Rev. Lett. 41, 1509 (1978).ADSCrossRefGoogle Scholar
- 5.K. Gloos et al.,Physica B 218, 169 (1996).ADSCrossRefGoogle Scholar
- 6.N.R. Werthamer, E. Helfand and P.C. Hohenberg,Phys. Rev. 147, 295 (1966).ADSCrossRefGoogle Scholar
- 7.F. Sharifi et al.,Phys. Rev. B 44, 12521 (1991).ADSCrossRefGoogle Scholar
- 8.M. Suzuki, K. Komorita and M. Nagano,J. Phys. Soc. Jap. 63, 1449 (1994).ADSCrossRefGoogle Scholar
- 9.M. Suzuki,Jpn. J. Appl. Phys. 32, 2640 (1993).ADSCrossRefGoogle Scholar
- 10.P. Szabó et al., to be published.Google Scholar