Neutrons and muons for topological quantum materials: exploring magnetic order

Conference item

Topological insulators become functional magnetic quantum materials once time-reversal symmetry is broken, enabling phenomena such as the quantum anomalous Hall effect and related chiral transport states. Over the past decade, we have pursued a systematic program to understand how magnetic order can be introduced, controlled, and quantitatively characterized in topological materials grown by molecular beam epitaxy. This contribution reviews our work on magnetic doping and magnetic proximity effects in (Bi,Sb)2 Te3based systems, with a particular emphasis on depth-resolved and local probes of magnetism. Using a combination of polarized neutron reflectometry, muon spin spectroscopy, and element-specific x-ray techniques, we have established where magnetic order resides, how homogeneous it is, and how it couples across interfaces. We show that magnetic doping often leads to intrinsically inhomogeneous magnetic states, while carefully engineered heterostructures can imprint or enhance magnetism in a controlled manner. Recent results on CrTe₂/Bi₂Te₃ heterostructures provide direct evidence for proximity-induced magnetism in a topological insulator without chemical doping. Together, these studies demonstrate how neutrons and muons provide essential insight into magnetic topological materials and guide the design of platforms for quantum and spintronic devices.

Authors: Heppell, E; Kinane, CJ; Caruana, AJ; Steinke, N-J; Liu, X

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: IEEE
• Host title: 2026 IEEE International Magnetic Conference - Short Papers (INTERMAG Short Papers)
• Pages: 1-2
• Publication date: 2026-07-14
• Event title: IEEE International Magnetics Conference (INTERMAG 2026)
• Event location: Manchester, UK
• Event website: https://intermag2026.org/
• Event start date: 2026-04-13
• Event end date: 2026-04-17
• DOI: 10.1109/intermagshortpapers68882.2026.11596456
• EISBN: 9798331557621
• ISBN: 9798331557638
• Language: English
• Keywords: printing; topological insulators; bismuth; business intelligence; doping; mesons; neutrons; displays; indexes; indexing