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Spin polarization of the electric current in half-metallic Co2MnSi Heusler thin films

J. Solano Córdova1,2,*, A. Friedel3,4, Q. Rossi1, J. Robert1, Y. Henry1, P. Pirro4, S. Petit-Watelot3, S. Andrieu3, and M. Bailleul1,†

  • *Contact author: jose.solano@fzu.cz
  • †Contact author: matthieu.bailleul@ipcms.unistra.fr
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Phys. Rev. B 114, 094436 – Published 27 August, 2026

DOI: https://doi.org/10.1103/w93y-w66w

Abstract

Using propagating spin wave spectroscopy we measure the spin wave Doppler shift in patterned MgO/Co2MnSi/MgO thin films and determine the degree of spin polarization of the electric current. Our measurements reveal that the current is fully spin polarized in the devices. This shows that the half-metallic character of the electron band structure translates into a fully spin polarized current flowing across the patterned films. Additionally, we measure a current-induced change of the spin-wave attenuation from which we estimate the nonadiabatic spin-transfer-torque parameter.

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References (44)

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Phys. Rev. B 114, 094436– Published 27 August, 2026
  • Received 4 June 2026
  • Accepted 12 August 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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