Random fields and apparent exchange bias in the dilute Ising antiferromagnet Fe0.6Zn0.4F2

D C Joshi; P Nordblad; R Mathieu

doi:10.1038/s41598-020-71533-6

Random fields and apparent exchange bias in the dilute Ising antiferromagnet Fe_0.6Zn_0.4F₂

Sci Rep. 2020 Sep 3;10(1):14588. doi: 10.1038/s41598-020-71533-6.

Authors

D C Joshi¹, P Nordblad², R Mathieu²

Affiliations

¹ Department of Materials Science and Engineering, Uppsala University, Box 35, 751 03, Uppsala, Sweden. [email protected].
² Department of Materials Science and Engineering, Uppsala University, Box 35, 751 03, Uppsala, Sweden.

Abstract

Random field induced spontaneous excess moments appear in field cooled single crystals of diluted Ising antiferromagnets. Here we report results from low temperature measurements of field cooled (including zero field) magnetic hysteresis loops parallel and perpendicular to the c-axis of a single crystal of composition Fe_0.6Zn_0.4F₂. We find that weak static ferromagnetic excess moments attained on field cooling give rise to an apparent exchange bias of the magnetic hysteresis loops, whose magnitude is controlled by temperature and the strength and direction of the cooling field. Random field induced temporal excess moments only become observable in cooling fields larger than 1 T applied along the c-axis direction of the Fe_0.6Zn_0.4F₂ single crystal.