Defect States in Time and Space Modulated Lattices
Abstract
Significant advancement in synthesized materials and fabrication enables photonic structures to mold photons in a broad range of frequencies. However, our needs for scientific, industrial, and defense applications call for more advanced structures with a higher degree of freedom, on-demand reconfigurability, and multi-functionalities, such as mirrorless unidirectional emission, ultrafast and long-range optical tunability, and controlled emission pattern, to name a few. Thus, searching for novel mechanisms and new geometries to control light propagation is inevitable. Here we propose an innovative approach, based on defect state embedded in a spatiotemporal modulated system, to obtain optical functionalities that enable us to engineer the direction, and/or pattern of light propagation, on demand. In our proposal, we break time-reversal symmetry which is obtained via the time-dependent modulation resulting in the generation of nonreciprocal defect state for an embedded defect. Such arrangement provides us with a powerful tool to control the photon propagation and obtain new functionalities. We expect that our proposed non-reciprocal defect modes can uniquely provide on-demand directionality and sensitivity which are missing in the existing technology. The proposal studies theoretically, and models numerically, electromagnetic properties of defect state embedded in structures with spatiotemporal modulations. Our research will investigate (i) the physics of linear Hermitian and non-Hermitian defects, and (ii) non-linear Hermitian and non-Hermitian defects to obtain 1) non-reciprocal localization of photons, 2) mirrorless unidirectional lasing modes, and 3) two-frequency nonlinear effects with applications such as non-reciprocal limiters. This project involves highly developed theoretical and modeling techniques to design new photonic architectures with extraordinary functionalities. The training of undergraduate and graduate students is an integral component of this project. The PIs have a long record of working with underrepresented minority students and will work with both undergraduate and graduate students as part of this project. The project will offer an excellent opportunity for Hispanic students to engage in research in STEM fields at The University of Texas Rio Grande Valley, the second largest Hispanic-Serving Institution in the country. It is the intention of this project to motivate and encourage the participating Hispanic students to go to graduate school by exposing them to cutting-edge research in applied science, hence assisting with the development of a skilled workforce for emerging photonics needs in the DoD.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 20, 2020
- Source ID
- W911NF2010276
Entities
People
- Hamidreza Ramezani
Organizations
- Army Contracting Command
- Office of the Secretary of Defense
- University of Texas Rio Grande Valley