Room-temperature spin pumping from canted antiferromagnet α-Fe2O3

Abstract

Spin pumping from canted antiferromagnets is a cutting-edge topic in modern spintronics. The interest for fundamental and applied research that these materials arouse is related to their unusual structure, namely, with a small canting of the magnetic sublattices, which is explained by the presence of the Dzyaloshinskii–Moriya interaction. Through this effect, it becomes possible to experimentally study quasi-ferromagnetic resonance spectra and spin pumping in the range of tens of GHz at room temperature. In this paper, an experimental and theoretical investigation of spin pumping from an antiferromagnet with weak ferromagnetism, α-Fe2O3, is carried out. The conversion of the precession of the magnetization vector, excited by an alternating magnetic microwave field, into a constant voltage is realized using the inverse spin Hall effect in the hematite/heavy metal structure. Using a constant magnetic field up to 5 kOe, the resonant frequency of such a detector is tunable over a wide range up to 32 GHz with potential sensitivity reaching 10.1 μV/W. Confirmation of the measurement of the spin current is the change in the sign of Vsp when the polarity of the constant magnetic field alters. We believe that these studies will make a major contribution to the understanding of the physics of the spin-pumping effect from antiferromagnets and will also help in the development of devices for quantum technologies and next-generation communication technologies.