Interface Physics and Applications in Topological Insulator-based Magnetic Heterostructures
Abstract
Major Goals: The main goals of this proposal are to experimentally realize novel topological insulator (TI)-based magnetic/antiferromagnetic heterostructures with comprehensive studies on their quantum physical properties. The interplay among band topology and symmetry and magnetism gives rise to more novel physics in such heterostructures. By interfacing the TI with some ferromagnets and antiferromagnets(AFM), the interfacial magnetic exchange can break the time-reversal-symmetry on the surface of the TI via exchange coupling or proximity effect. In this report, we focus on new types of TI/AFM heterostructures and superlattices. Via structural engineering and molecular beam epitaxy, both composition and thickness of TI and AFM layers can be accurately controlled to provide a versatile experimental platform for exploring the exchange interaction between the two material systems. The present study may result in possible new effects and various breakthroughs as well as applications, for example, the giant SOT in TIs and ultrafast resonance frequency in AFM will help to realize various low power consumption spintronic devices, such as RF/THz oscillators based on spin-wave and super-spin currents. This work will also generate the necessary knowledge and skills to enable the next-generation of information process technologies. Accomplishments: In this report, we achieved high quality AFM/MTI heterostructures and superlattices using molecular beam epitaxy method. The AFM material CrSb and MTI can form high quality interfaces to facilitate our study. We successfully realized emergent interfacial magnetic effects through the exchange coupling between topological Dirac Fermions and AFM order mediated by AFM spins. By using the state-of-art polarized neutronreflectometry technique with collaboration with NIST, we revealed origin of the interfacial magnetic coupling effect between MTIs ferromagnetic order and CrSbs AFM order.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 18, 2018
- Accession Number
- AD1067353
Entities
People
- Kang L. Wang
Organizations
- University of California, Los Angeles