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arXiv · 1205.0112

Carrier Transport in Magnesium Diboride: Role of Nano-inclusions

A. M. Awasthi·S. Bhardwaj·V. P. S. Awana·A. Figini Albisetti·G. Giunchi·A. V. Narlikar
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Abstract

Anisotropic-gap and two-band effects smear out the superconducting transition (Tc) in literature reported thermal conductivity of MgB2, where large electronic contributions also suppress anomaly-manifestation in their negligible phononic-parts. Present thermal transport results on scarcely explored specimens featuring nano-inclusions exhibit a small but clear Tc-signature, traced to relatively appreciable phononic conduction, and its dominant electronic-scattering. The self-formed MgO as extended defects strongly scatter the charge carriers and minutely the phonons with their longer-mean-free-path near Tc. Conversely, near room temperature, the shorter-dominant-wavelength phonon's transport is hugely affected by these nanoparticles, undergoing ballistic to diffusive crossover and eventually entering the Ioffe-Regel mobility threshold regime.

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A. M. Awasthi, S. Bhardwaj, V. P. S. Awana, A. Figini Albisetti, G. Giunchi, A. V. Narlikar. 2012-05-01. Carrier Transport in Magnesium Diboride: Role of Nano-inclusions. https://doi.org/10.1063/1.4821135

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