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Role of Structural Defects on the Half-Metallic Character of Heusler Alloys and Their Junctions with Ge and GaAs

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Half-metallic Alloys

Part of the book series: Lecture Notes in Physics ((LNP,volume 676))

Abstract

Heusler–alloys, such as Co2MnGe and Co2MnSi, predicted from firstprinciples to be half–metallic, have recently attracted great attention for spininjection purposes. However, spin polarizations of only 50%–60% were experimentally obtained for Heusler thin films – a decrease attributed to defects in the Mn and Co sublattices. We performed ab–initio FLAPW calculations in order to determine the effects of several types of defects (Co and Mn antisites, atomic swaps, etc.) on the electronic and magnetic properties of the bulk Heusler compounds. Our findings, in general agreement with experiments, show that Mn antisites have the lowest formation energy and retain the half–metallic character. On the other hand, Co antisites have a slightly higher formation energy and a dramatic effe

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Authors and Affiliations

  1. CASTI-INFM Regional Lab. and Dip. Fisica, Univ. L'Aquila, 67010 Coppito(Aq), Italy

    Silvia Picozzi & Alessandra Continenza

  2. Dept. of Physics and Astronomy, Northwestern University, 60208 Evanston, Il, USA

    Arthur J. Freeman

Authors
  1. Silvia Picozzi
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  2. Alessandra Continenza
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  3. Arthur J. Freeman
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I. Galanakis P.H. Dederichs

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Picozzi, S., Continenza, A., J. Freeman, A. Role of Structural Defects on the Half-Metallic Character of Heusler Alloys and Their Junctions with Ge and GaAs. In: Galanakis, I., Dederichs, P. (eds) Half-metallic Alloys. Lecture Notes in Physics, vol 676. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11506256_2

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  • DOI: https://doi.org/10.1007/11506256_2

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  • Print ISBN: 978-3-540-27719-4

  • Online ISBN: 978-3-540-31517-9

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