Nonlocal Spin Photonics in Weyl Semiconductor Tellurium
Abstract
Over the last decade, the frontier of topological materials have expanded significantly beyond insulators to include ferromagnets, semi-metals and spin liquids. The theoretical principles and insights guiding these discoveries arise from relativistic analogies tothe Dirac equation, Weyl equation as well as topological field theories (eg: Chern-Simons gauge theory). The experimental evidence of topology is gathered through techniques such as angle resolved photo-emission spectroscopy (ARPES) and low frequency/DC transportmeasurements. While a number of novel electromagnetic phenomena like the Axionic response have been proposed in topological materials over the past decade, these predictions are made mostly at low frequencies (from microwave regions to THz) which limit their applications in photonics. The goal of this three-year ONR program is to develop theory-driven-experimental insights on topological materials physics towards infrared/optical light-matter interaction. In this project, we put forth the next frontier of effects in light-matter interactions in the nonlocal regime. Non-local photonic responses in atomistic topological materials have the potential to unlock nanoscale applications with a new degree of freedom - spatial dispersion. We will use a theory-driven experimental approachto investigate the nonlocal photonics phenomena in a class of topological materials - Weyl semiconductors; providing foundational new degrees of freedom for tailoring atomistic light-matter interactions. Our choice of platform is a crucial advance since it is transparent, lossless and also has a broadband non-local response arising from the atomistic screw symmetry of the Weyl semiconductor crystal structure. Another novel aspect of our work is that the eigenstates for photons propagating in such systems are spin-polarized where the handedness of light is set by the screw symmetry of the atomic lattice structure Our three-year effort for ONR will focus on the emerging Weyl semiconductor Tellurium (Te) as an ideal platform to explore atomistic nonlocal properties including an axionic response pushing it for the first time to the infrared and optical frequencies.The long-term impact of this work will be in the development of new metrological tools specific to non-local interactions in topological materials and our research will also lay thefoundations for discovering novel pico-electrodynamic phenomena in materials.This abstract is approved for Public Release.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 24, 2023
- Source ID
- N000142312707
Entities
People
- Zubin Jacob
Organizations
- Office of Naval Research
- Purdue University
- United States Navy