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Tunneling spectroscopy in small grains of superconducting MgB2

Gabino Rubio-Bollinger·Hermann Suderow·Sebastian Vieira
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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.

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Gabino Rubio-Bollinger, Hermann Suderow, Sebastian Vieira. 2001-04-04. Tunneling spectroscopy in small grains of superconducting MgB2. https://doi.org/10.1103/physrevlett.86.5582

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