Tunneling spectroscopy and magnetization measurements of the superconductor properties of MgB2
نویسندگان
چکیده
Cryogenic scanning tunneling microscopy and magnetization measurements were used to study the superconducting properties of MgB2. The magnetization measurements show a sharp superconductor transition at Tc = 39K, in agreement with previous works. The tunneling spectra exhibit BCS gap structures, with gap parameters in the range of 5 to 7 meV, yielding a ratio of 2∆/kBTc ∼ 3− 4. This suggests that MgB2 is a conventional BCS s-wave superconductor, either in the weak-coupling or in the ‘intermediate-coupling’ regime. Typeset using REVTEX e-mail: [email protected] email: [email protected]
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