Exchange‐Biased Quantum Anomalous Hall Effect
Abstract
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)2Te3 (CBST) grown on an uncompensated antiferromagnetic insulator Al‐doped Cr2O3. Through polarized neutron reflectometry (PNR), a strong exchange coupling is found between CBST and Al‐Cr2O3 surface spins fixing interfacial magnetic moments perpendicular to the film plane. The interfacial coupling results in an exchange‐biased QAH effect. This study further demonstrates that the magnitude and sign of the exchange bias can be effectively controlled using a field training process to set the magnetization of the Al‐Cr2O3 layer. It demonstrates the use of the exchange bias effect to effectively manipulate the QAH state, opening new possibilities in QAH‐based spintronics.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jun 27, 2023
- Source ID
- 10.1002/adma.202300391
Entities
People
- Alexander J. Grutter
- Brian B Maranville
- Chris Eckberg
- Eve Emmanouilidou
- Gang Qiu
- Kang L. Wang
- Lei Pan
- Masashi Sahashi
- Megan E. Holtz
- Ni Ni
- Patrick Quarterman
- Peng Deng
- Peng Zhang
- Purnima P. Balakrishnan
- Su Kong Chong
- Tomohiro Nozaki
Organizations
- Army Research Office
- National Institute of Standards and Technology
- National Science Foundation
- Office of Basic Energy Sciences
- Office of Science
- Tohoku University
- United States Army Research Laboratory
- United States Department of Energy
- University of California
- University of California, Los Angeles