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Experimental study of electron-phonon properties in ZrB 2

  • E. ForzaniEmail author
  • K. Winzer
Solid and Condensed State Physics

Abstract.

High quality samples and absence of superconductivity down to 40 mK make of ZrB2 the best normal state reference system for the superconducting isostructural MgB2. Actually, the question of pairing has to be focused on the electron-phonon interaction in the normal state. After presenting the resistivity measurements of ZrB2, we explain the details of the Bloch-Grüneisen and Einstein models used to deduce the first results. We then compare experimental de Haas-van Alphen effect data with theoretical Fermi surfaces to present additional results on electron quasi-particle renormalization. The estimations reveal an isotropic and negligible coupling constant of in average \(\left\langle \lambda_{tr} \right\rangle=\) 0.145. The contribution of the coupling to the optical phonon modes is 0.082, in contrast to the known larger coupling of 0.283 [3] to the E2g phonon mode in MgB2.

PACS.

71.18.+y Fermi surface: calculations and measurements; effective mass, g factor 71.38.-k Polarons and electron-phonon interactions 72.10.-d Theory of electronic transport; scattering mechanisms 74.25.Fy Transport properties 

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Copyright information

© EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006

Authors and Affiliations

  1. 1.Erstes Physikalisches Institut, Georg-August-Universität GöttingenGöttingenGermany

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