Large unidirectional spin Hall and Rashba−Edelstein magnetoresistance in topological insulator/magnetic insulator heterostructures
Abstract
The unidirectional spin Hall and Rashba−Edelstein magnetoresistance is of great fundamental and practical interest, particularly in the context of reading magnetization states in two-terminal spin–orbit torque memory and logic devices due to its unique symmetry. Here, we report large unidirectional spin Hall and Rashba−Edelstein magnetoresistance in a new material family—magnetic insulator/topological insulator Y3Fe5O12/Bi2Se3 bilayers. Such heterostructures exhibit a unidirectional spin Hall and Rashba−Edelstein magnetoresistance that is about an order of magnitude larger than the highest values reported so far in all-metal Ta/Co bilayers. The polarized neutron reflectometry reveals a unique temperature-dependent magnetic intermediary layer at the magnetic insulator–substrate interface and a proximity layer at the magnetic insulator–topological insulator interface. These polarized neutron reflectometry findings echo the magnetoresistance results in a comprehensive physics picture. Finally, we demonstrate a prototype memory device based on a magnetic insulator/topological insulator bilayer, using unidirectional spin Hall and Rashba−Edelstein magnetoresistance for electrical readout of current-induced magnetization switching aided by a small Oersted field.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 20, 2022
- Source ID
- 10.1063/5.0073976
Entities
People
- Alexander J. Grutter
- Brian J Kirby
- James Kally
- Jian-Ping Wang
- Julie Borchers
- Mingzhong Wu
- Nitin Samarth
- Patrick Quarterman
- Protyush Sahu
- Tao Liu
- Timothy Pillsbury
- Yang Lv
Organizations
- Colorado State University
- Defense Advanced Research Projects Agency
- National Institute of Standards and Technology
- National Science Foundation
- Pennsylvania State University
- Semiconductor Research Corporation
- University of Minnesota