Superconducting energy gap distribution of MgB${}_2$ investigated by point-contact spectroscopy

Abstract

We performed point-contact spectroscopy on the binary superconductor MgB${}_2$. The differential conductance shows gap-related structures which vary in width and position from contact to contact. The distribution of energy gaps shows a distinct accumulation around 1.7 and 7 meV which is associated with the occurrence of a small and a large energy gap in MgB${}_2$. While with increasing $T$ the structure in $dI/dV$ associated with the small gap is present up to $T_C$, in magnetic field it is suppressed well below $B_{c2}$.

4 pages, 6 figures

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Cited by in corpus (12)

• Specific heat of MgB${}_2$ in a one- and a two-band model from first-principles calculations
• Probing multiband superconductivity by point-contact spectroscopy
• Specific heat of single crystal MgB_2: a two-band superconductor with two different anisotropies
• Thermal conductivity of single crystalline MgB_2
• Morphology of the Superconducting Vortex Lattice in Ultra-Pure Niobium
• Point-contact spectroscopy of MgB2
• Break-Junction Tunneling on MgB_2
• Superconducting energy gap distribution in c-axis oriented MgB${}_2$ thin film from point contact study
• Phonon structure in I-V characteristic of MgB${}_2$ point-contacts
• A second superconducting energy gap of Nb_3Sn observed by breakjunction point-contact spectroscopy
• Heat capacity of mesoscopically disordered superconductors:implications to MgB${}_2$
• Electronic structure of single-crystalline Mg${}_x$Al${}_{1-x}$B${}_2$ probed by x-ray diffraction multipole refinements and polarization-dependent x-ray absorption spectroscopy