Effect of Co-Fe substitutions on the room-temperature spin polarization in Co_3-xFe_xSi Heusler-compound films

TL;DR

This study investigates how substituting Fe for Co in Co_3-xFe_xSi Heusler films affects their magnetic properties and room-temperature spin polarization, confirming the substitution's direct impact on spin polarization.

Contribution

It provides experimental evidence that Co-Fe substitution in Co_3-xFe_xSi Heusler compounds influences their room-temperature spin polarization.

Findings

Co-Fe substitution confirmed by Mossbauer spectroscopy

Magnetic moment varies with Co-Fe substitution

Spin polarization at room temperature is affected by substitution

Abstract

Using low-temperature molecular beam epitaxy, we study substitutions of Fe atoms for Co ones in Co_3-xFe_xSi Heusler-compound films grown on Si and Ge. Even for the low-temperature grown Heusler-compound films, the Co-Fe atomic substitution at A and C sites can be confirmed by the conversion electron M"ossbauer spectroscopy measurements. As a result, the magnetic moment and room-temperature spin polarization estimated by nonlocal spin-valve measurements are systematically changed with the Co-Fe substitutions. This study experimentally verified that the Co-Fe substitution in Co_3-xFe_xSi Heusler compounds can directly affect the room-temperature spin polarization.