1. Tunneling density of states of MgB 2 : evidence for a dominant π‐band contribution
- Author
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Mikhail Belogolovskii, A. V. Abal'oshev, Stanislaw J. Lewandowski, V. Yu. Tarenkov, and A. I. D’yachenko
- Subjects
Superconductivity ,Nonlinear system ,chemistry.chemical_compound ,chemistry ,Condensed matter physics ,Condensed Matter::Superconductivity ,Niobium ,Density of states ,Magnesium diboride ,chemistry.chemical_element ,Crystallite ,Spectroscopy ,Quantum tunnelling - Abstract
Weakly-transmitting junctions usable for tunneling spectroscopy experiments were fabricated from polycrystalline bulk samples of magnesium diboride with a niobium counter-electrode. A strong nonlinear conductance-versus-voltage behavior for voltages above the values corresponding to the energy gaps of the electrodes was interpreted as a fingerprint of the electron-phonon interaction in superconducting MgB2. A partial Eliashberg spectral function α2(ω)F(ω) was extracted from the data by the numeric inversion of the standard strong-coupling Eliashberg equations. In a full agreement with recent theoretical simulations for magnesium diboride [1], we have observed a dominant contribution from the π-band of this two-band superconductor. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
- Published
- 2005
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