Magnetism of (Dy0.5Er0.5)Al2 single crystal in ac and dc magnetic fields

Abstract

The temperature (4.2–90K), ac magnetic field (1.25–50Oe), frequency (5–125Hz), and bias dc magnetic field (0–10kOe) dependencies of the real and imaginary components of the ac magnetic susceptibility, and the temperature (4.2–250K) and dc magnetic field (0.1–50kOe) dependencies of the dc magnetic susceptibility and magnetization of a (Dy0.5Er0.5)Al2 single crystal have been studied. Isothermal magnetization measurement in a dc magnetic field indicates that (Dy0.5Er0.5)Al2 orders ferromagnetically at 37K. The ac and dc magnetic susceptibilities of (Dy0.5Er0.5)Al2 exhibit a similar behavior in the paramagnetic region but quite different behaviors in the ferromagnetic state. Both the real and imaginary components of the ac magnetic susceptibility are sensitive to the applied ac magnetic field, the crystallographic direction, and the bias magnetic field, showing that domain wall dynamics mainly account for the response to the ac magnetic field. The contributions to the magnetization process arise from the magnetically ordered Dy and Er sublattices and depend upon the single-ion anisotropy of the Dy and Er ions.