Probing the electron-phonon coupling in MgB2 through magnetoresistance measurements in neutron irradiated thin films

M. Monni; I. Pallecchi; C. Ferdeghini; V. Ferrando; A. Floris; E. Galleani d'Agliano; E. Lehmann; I. Sheikin; C. Tarantini; X. X. Xi; S. Massidda; M. Putti

doi:10.1209/0295-5075/81/67006

arXiv · 0706.3591

Probing the electron-phonon coupling in MgB2 through magnetoresistance measurements in neutron irradiated thin films

M. Monni·I. Pallecchi·C. Ferdeghini·V. Ferrando·A. Floris·E. Galleani d'Agliano·E. Lehmann·I. Sheikin·C. Tarantini·X. X. Xi·S. Massidda·M. Putti

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Abstract

We report magnetoresistance (MR) measurements on MgB2 and the corresponding full account from ab-initio calculations; we suggest that this combination can be a useful tool to probe electron- phonon coupling. We obtain good quantitative agreement between high field measurements on neutron irradiated epitaxial thin films and calculations within Bloch-Boltzmann transport theory over a wide range of magnetic fields (0-28 T) and temperatures (40-300 K), and as a function of the field orientation. The crossovers between in-plane and out-of-plane MR, experimentally observed as a function of either disorder or temperature are well reproduced indicating that disorder and interaction with phonons strongly affect the scattering rate of s-carriers.

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M. Monni, I. Pallecchi, C. Ferdeghini, V. Ferrando, A. Floris, E. Galleani d'Agliano, E. Lehmann, I. Sheikin, C. Tarantini, X. X. Xi, S. Massidda, M. Putti. 2007-06-25. Probing the electron-phonon coupling in MgB2 through magnetoresistance measurements in neutron irradiated thin films. https://doi.org/10.1209/0295-5075/81/67006

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