Thermal conductivity of MgB${}_2$ in the superconducting state

Abstract

We present thermal conductivity measurements on very pure and dense bulk samples, as indicated by residual resistivity values as low as 0.5 mW cm and thermal conductivity values higher than 200 W/mK. In the normal state we found that the Wiedemann Franz law, in its generalized form, works well suggesting that phonons do not contribute to the heat transport. The thermal conductivity in the superconducting state has been analysed by using a two-gap model. Thank to the large gap anisotropy we were able to evaluate quantitatively intraband scattering relaxation times of $\pi$ and $\sigma$ bands, which depend on the disorder in different way; namely, as the disorder increases, it reduces more effectively the relaxation times of $\pi$ than of $\sigma$ bands, as suggested by a recent calculation [1].

12 pages, 5 figures

References in corpus (10)

• Beyond Eliashberg superconductivity in MgB2: anharmonicity, two-phonon scattering, and multiple gaps
• Specific Heat of Mg ^{11}B_2
• Thermodynamic and Transport Properties of Superconducting $M{g}^{10}{B}_2$
• First-Principles Calculation of the Superconducting Transition in MgB2 within the Anisotropic Eliashberg Formalism
• Two-gap superconductivity in MgB${}_2$: clean or dirty?
• Phenomenological two-gap model for the specific heat of MgB_2
• Multiband model for tunneling in MgB2 junctions
• Multiband model for penetration depth in MgB2
• Thermal conductivity of single crystalline MgB_2
• Strong Electron-Phonon Coupling in Superconducting MgB${}_2$: A Specific Heat Study

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• Physical Property Characterization of Bulk MgB2 Superconductor
• Influence of carbon substitution on the heat transport in single crystalline MgB2
• Study on the formation of MgB2 phase
• Thermal Transport for Probing Quantum Materials
• Upper Critical Fields up to 60T in Dirty Magnesium Diboride Thin Films
• Thermal conductivity of Al-doped MgB2: Impurity scattering and the validity of the Wiedemann-Franz law
• Theory of vortices in hybridized ballistic/diffusive-band superconductors
• Anisotropic normal-state properties of the MgB2 superconductor
• Thermal conductivity and stability of commercial MgB${}_2$ conductors
• Ballistic and diffusive: theory of vortices in the two-band superconductor MgB2
• Carrier Transport in Magnesium Diboride: Role of Nano-inclusions
• Hump Structure below Tc in the thermal conductivity of MgB2 superconductor
• Thermal properties of MgB2: the effect of disorder on gap amplitudes and relaxation times of p and s bands