TOPOLOGY AND MAGNETISM IN CHIRAL CRYSTALS
Abstract
Recent theoretical works have demonstrated a universal topological character in materials with well-defined lattice chirality (handedness). The universality theorem states that any non-magnetic chiral crystal will automatically acquire Kramers-Weyl nodes. However, it is not clear how these universal Weyl nodes and their exotic electrical and optical properties evolve in the presence of magnetism. The goal of this proposal is to create a nexus of topology and magnetism in chiral structures by systematically identifying and growing such crystals. The systematic approach includes (i) identifying candidate materials based on symmetry considerations, (ii) implementing advanced crystal growth techniques to solidify crystals with large chiral domains, and (iii) carefully characterizing their anomalous transport properties. Magnetism is included in two steps by first, including magnetic dopants in non-magnetic chiral lattices (perturbative approach), and second, growing purely magnetic chiral crystals (non-perturbative approach). The material synthesis and characterization efforts will be combined with first principles calculations and theoretical symmetry analyses in collaboration with the Taiwan partner. The immediate outcome of the project is several families of magnetic chiral crystals with applicable electrical, magnetic, and optical properties such as quantized anomalous Hall effect, circular photo-galvanic effect, and topological magnetic excitations. Appropriate collaborations are envisioned with experts in photo-emission and magneto-optical spectroscopy on single crystals and devices. In the long run, the methodology developed here will guide future endeavors in materials science to grow sizable chiral crystals
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Nov 17, 2022
- Source ID
- FA23862114059
Entities
People
- Fazel Tafti
Organizations
- Air Force Office of Scientific Research
- Boston College
- United States Air Force