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Temperature and Field Dependence of the Energy Gap of MgB2/Pb planar junction

Mohamed H. Badr·Mario Freamat·Yuri Sushko·K. -W. Ng
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Abstract

We have constructed MgB2/Pb planar junctions for both temperature and field dependence studies. Our results show that the small gap is a true bulk property of MgB2 superconductor, not due to surface effects. The temperature dependence of the energy gap manifests a nearly BCS-like behavior. Analysis of the effect of magnetic field on junctions suggests that the energy gap of MgB2 depends non-linearly on the magnetic field. Moreover, MgB2 has an upper critical field of 15 T, in agreement with some reported Hc2 from transport measurements.

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Mohamed H. Badr, Mario Freamat, Yuri Sushko, K. -W. Ng. 2001-10-19. Temperature and Field Dependence of the Energy Gap of MgB2/Pb planar junction. https://doi.org/10.1103/physrevb.65.184516

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