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arXiv · 1706.04670

Temperature-dependent Gilbert damping of Co2FeAl thin films with different degree of atomic order

Ankit Kumar·Fan Pan·Sajid Husain·Serkan Akansel·Rimantas Brucas·Lars Bergqvist·Sujeet Chaudhary·Peter Svedlindh
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Abstract

Half-metallicity and low magnetic damping are perpetually sought for in spintronics materials and full Heusler alloys in this respect provide outstanding properties. However, it is challenging to obtain the well-ordered half-metallic phase in as-deposited full Heusler alloys thin films and theory has struggled to establish a fundamentals understanding of the temperature dependent Gilbert damping in these systems. Here we present a study of the temperature dependent Gilbert damping of differently ordered as-deposited Co2FeAl full Heusler alloy thin films. The sum of inter- and intraband electron scattering in conjunction with the finite electron lifetime in Bloch states govern the Gilbert damping for the well-ordered phase in contrast to the damping of partially-ordered and disordered phases which is governed by interband electronic scattering alone. These results, especially the ultralow room temperature intrinsic damping observed for the well-ordered phase provide new fundamental insights to the physical origin of the Gilbert damping in full Heusler alloy thin films.

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Ankit Kumar, Fan Pan, Sajid Husain, Serkan Akansel, Rimantas Brucas, Lars Bergqvist, Sujeet Chaudhary, Peter Svedlindh. 2017-06-14. Temperature-dependent Gilbert damping of Co2FeAl thin films with different degree of atomic order. https://doi.org/10.1103/physrevb.96.224425

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