Tunneling spectroscopy in small grains of superconducting MgB2

Abstract

We report on tunneling spectroscopy experiments in small grains of the new binary intermetallic superconductor MgB2. Experiments have been performed at 2.5 K using a low temperature scanning tunneling microscope. Good fit to the BCS model is obtained, with a gap value of 2 meV. In the framework of this model, this value should correspond to a surface critical temperature of 13.2 K. No evidence of gap anisotropy has been found.

3 pages with 3 figures, resubmitted to Phys.Rev.Lett 28-February

References in corpus (2)

• Boron Isotope Effect in Superconducting MgB${}_2$
• Hole Superconductivity in $Mg{B}_2$: a high $T_c$ cuprate without Cu

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