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Electron-Phonon Interaction in NbB_2 : A Comparison with MgB_2

Prabhakar P. Singh
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Abstract

We present a comparison of electron-phonon interaction in NbB_2 and MgB_2, calculated using full-potential, density-functional-based methods in P6/mmm crystal structure. Our results, described in terms of (i) electronic structure, (ii) phonon density of states F(ω), (iii) Eliashberg function α^2F(ω), and (iv) the solutions of the isotropic Eliashberg gap equation, clearly show significant differences in the electron-phonon interaction in NbB_2 and MgB_2. We find that the average electron-phonon coupling constant λis equal to 0.59 for MgB_2 and 0.43 for NbB_2, leading to superconducting transition temperature T_c of around 22 K for MgB_2 and 3 K for NbB_2.

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Prabhakar P. Singh. 2002-10-04. Electron-Phonon Interaction in NbB_2 : A Comparison with MgB_2. https://doi.org/10.1016/s0038-1098(02)00819-0

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