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arXiv · 0711.2476

Non-quasiparticle states in Co$_2$MnSi evidenced through magnetic tunnel junction spectroscopy measurements

L. Chioncel·Y. Sakuraba·E. Arrigoni·M. I. Katsnelson·M. Oogane·Y. Ando·T. Miyazaki·E. Burzo·A. I. Lichtenstein
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Abstract

We investigate the effects of electronic correlations in the full-Heusler Co$_2$MnSi, by combining a theoretical analysis of the spin-resolved density of states with tunneling-conductance spectroscopy measurements using Co$_2$MnSi as electrode. Both experimental and theoretical results confirm the existence of so-called non-quasiparticle states and their crucial contribution to the finite-temperature spin polarisation in this material.

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L. Chioncel, Y. Sakuraba, E. Arrigoni, M. I. Katsnelson, M. Oogane, Y. Ando, T. Miyazaki, E. Burzo, A. I. Lichtenstein. 2008-07-23. Non-quasiparticle states in Co$_2$MnSi evidenced through magnetic tunnel junction spectroscopy measurements. https://doi.org/10.1103/physrevlett.100.086402

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