Yttrium Iron Garnet Film-Based Magnonic Topological Insulators
Abstract
A magnonic topological insulator is the magnetic analogue to an electronic topological insulator. The band structure in a magnonic topological insulator consists of (1) conventional bands separated by band gaps for bulk magnons and (2) magnonic edge states within the gaps that bridge the bulk bands. As with electronic topological insulators, the edge states in magnonic topological insulators are protected by the topology of the bulk bands. Such topological protection gives rise to the following exotic features of the magnonic edge states: (1) unidirectional transport, (2) edge localization, and (3) no backscattering. These special features make the edge modes Òdissipation freeÓ and robust against perturbations. In this three-year program, we will develop magnonic topological insulators that consist of yttrium iron garnet (YIG) thin films either implanted with periodic ferromagnetic nanopillars or etched with periodic triangular nanoholes. Due to mesoscopic symmetry breaking, such YIG-based structures are predicted, theoretically and numerically, to host topologically protected magnonic edge states. Our goal is to achieve the experimental realization of such YIG-based magnonic topological insulators and topological edge states therein. We also plan to demonstrate topological edge state-enabled magnonic devices, including magnonic diodes, splitters, and interferometers. With this program, we will not only realize critical demonstrations of magnonic topological insulator physics, but will also lay the groundwork for new classes of topological magnonic devices.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Aug 17, 2022
- Source ID
- W911NF2210173
Entities
People
- Mingzhong Wu
Organizations
- Army Contracting Command
- Colorado State University
- United States Army