Systematic study of the two band/two gap superconductivity in carbon-substituted MgB2 by point-contact spectroscopy

Abstract

Point-contact measurements on the carbon-substituted Mg(B${}_{1-x}$C${}_x$)${}_2$ filament/powder samples directly reveal a retention of the two superconducting energy gaps in the whole doping range from $x=0$ to $x\approx 0.1$. The large gap on the $\sigma$-band is decreased in an essentially linear fashion with increasing the carbon concentrations. The changes in the the small gap ${\Delta }_{\pi }$ up to 3.8 % C are proportionally smaller and are more difficult to detect but for the heavily doped sample with $x\approx 0.1$ and $T_c=22$ K both gaps are still present, and significantly reduced, consistent with a strong essentially linear, reduction of each gap with the transition temperature.

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Cited by in corpus (23)

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• The different development of the anisotropic upper critical field in MgB2 by aluminum and carbon doping
• Thermodynamics of Two - Band Superconductors: The Case of MgB${}_2$
• Evidence for Single-gap Superconductivity in Mg(B_{1-x}C_x)_2 Single Crystals with x=0.132 from Point-Contact Spectroscopy
• Carbon-substitution dependent multiple superconducting gap of MgB${}_2$: a "sub-meV" resolution photoemission study
• Point-contact spectroscopy of Al- and C-doped MgB2. Superconducting energy gaps and scattering studies
• Influence of carbon substitution on the heat transport in single crystalline MgB2
• Proximity and Josephson effects in microstructures based on multiband superconductors
• A Study of Carbon Substitutions in MgB_2 within the two-band Eliashberg theory
• Comment on: "Band Filling and Interband Scattering Effects in MgB2: Carbon versus Aluminium Doping"
• On Heavy Carbon Doping of MgB${}_2$
• Electron-phonon coupling and two-band superconductivity of Al- and C-doped MgB2
• Superconducting properties of nanocrystalline MgB${}_2$
• Role of interband scattering in neutron irradiated MgB${}_2$ thin films by Scanning Tunneling Spectroscopy measurements
• Theory of vortices in hybridized ballistic/diffusive-band superconductors
• Raman Scattering Investigation of Electron Phonon Coupling in Carbon substituted MgB2
• Effects of Neutron Irradiation on Carbon Doped MgB2 Wire Segments
• Superconductivity in two-band systems with variable charge carrier density. The case of MgB2
• Features of Excess Conductivity Behavior in a Magnetic Superconductor Dy${}_{0.6}$Y${}_{0.4}$Rh${}_{3.85}$Ru${}_{0.15}$B${}_4$
• Abrikosov flux-lines in two-band superconductors with mixed dimensionality
• Is Delta_{pi}-gap-only superconductivity possible in Mg_{1-x}Al_{x}B_{2} and Mg(B_{1-y}C_{y})_{2} alloys?