Exchange-Biased Quantum Anomalous Hall Effect.

The quantum anomalous Hall (QAH) effect is characterized by a dissipationless chiral edge state with a quantized Hall resistance at zero magnetic field. Manipulating the QAH state is of great importance in both the understanding of topological quantum physics and the implementation of dissipationless electronics. Here, the QAH effect is realized in the magnetic topological insulator Cr-doped (Bi,Sb) Te (CBST) grown on an uncompensated antiferromagnetic insulator Al-doped Cr O .

Observation of Quantum Anomalous Hall Effect and Exchange Interaction in Topological Insulator/Antiferromagnet Heterostructure.

Integration of a quantum anomalous Hall insulator with a magnetically ordered material provides an additional degree of freedom through which the resulting exotic quantum states can be controlled. Here, an experimental observation is reported of the quantum anomalous Hall effect in a magnetically-doped topological insulator grown on the antiferromagnetic insulator Cr O . The exchange coupling between the two materials is investigated using field-cooling-dependent magnetometry and polarized neutron reflectometry.

Parasitic Magnetism in Magnetoelectric Antiferromagnet.

Parasitic magnetism plays an important role in magnetoelectric spin switching of antiferromagnetic oxides, but its mechanism has not been clearly investigated. Unlike the widely obtained surface boundary magnetization in magnetoelectric CrO antiferromagnet, we previously reported that Al doping could produce volume-dependent parasitic magnetism () in CrO with the remaining magnetoelectric effect and antiferromagnetic properties. In this work, we systematically investigated the magnetic properties of in CrO through its different exchange coupling characteristics with the ferromagnet at various conditions.

The dependence of nano-contact magnetoresistance on the bulk scattering spin asymmetry in CoFe alloys with oxidation impurities.

Nano-contact magnetoresistance (NCMR) spin-valves (SVs) using an AlO nano-oxide-layer (NOL) have numerous nanocontacts in the thin AlO oxide layer. The NCMR theoretically depends on the bulk scattering spin asymmetry ([Formula: see text]) of the ferromagnetic material in the nanocontacts. To determine the relationship between NCMR and [Formula: see text], we investigated the dependence of NCMR on the composition of the ferromagnetic material CoFe.