Mesoscopic and Quantum Engineered III-Nitride Nonlinear Metasurfaces
Abstract
The central objective of the proposed research is to develop the fundamental understanding and technical expertise needed to produce III-Nitride nonlinear quantum well (QW) metasurfaces with novel, optimized functionality. Despite rapid progress in the field of nonlinear metasurfaces, investigations of III-Nitride (i.e., GaN-based) nonlinear metasurfaces are lacking. The use of GaN-based metasurface platforms provides two main advantages compared to existing paradigms which primarily focus on bulk effects in centrosymmetric materials (e.g., Au or Si) or noncentrosymmetric III-V semiconductors (e.g., GaAs, AlAs, GaP). Firstly, the wide-bandgap of GaN allows for operation well into the UV portion of the electromagnetic spectrum. Secondly, the GaN platform allows for integration of quantum wells (QWs) to enhance or localize the nonlinear light-matter interaction. In this project we will develop and exploit quantum, mesoscopic, and classical engineering. Quantum Engineering is enabled by integration of quantum wells to create, enhance, or localize the nonlinear light-matter interaction. Mesoscopic engineering is enabled by the fundamental interplay between different material system Xi(2) tensors and metasurface-engineered fields. Classical engineering is enabled by designing and optimizing metasurface engineered fields for a given mesoscopic- and/or quantum-engineered nonlinear light-matter interaction. The proposed research buildsoff prior ONR-funded development of energy-momentum spectroscopy measurement techniques, growth and fabrication of GaN-based QW metasurfaces, and robust simulation and optimization methods. Research efforts are divided into three themes: 1) nonlinear wide-angle energy-momentum spectroscopy, 2) mesoscopic engineering of second harmonic generation (SHG) via tensorial electromagnetics, and 3) quantum engineering of resonant SHG and two-photon absorption (TPA) in GaN-based QWs. In theme 1 we will develop and calibrate a novelnonlinear wide-angle energy-momentum spectroscopy system that enables control of the energy and incident 2D momentum vector of the excitation source and measurements of the energy and momentum of nonlinear-generated light. In "wide-angle" measurements we derive significant benefit by exciting and/or measuring beyond the critical angle. In theme 2, we will develop experimentally-validated understanding of the interplay between different material Xi(2) tensors and metasurface-engineered fields. We will then employ learning algorithms to design, fabricate, and demonstrate doubly resonant mode-matched SHG metasurfaces that leverage the wide bandgap of GaNto achieve radiation-limited Q-factors at both the fundamental and second harmonic. In theme 3, we will investigate interband SHG and TPA resonances in GaN-based QWs and use QW nonlinearities to enhance or localize the nonlinear light-matter interaction. Specifically, we will use QW nonlinearities to achieve phased-array metasurface-mediated SHG and exploitnonlinear energy-momentum spectroscopy to investigate fundamentals of QW nonlinearities The proposed research program will provide new classes of nonlinear optical methods, materials and metasurface optics with demonstrable applications of relevance to Navy and DOD objectives. Most generally, this program addresses the Navy s desire to "understand, design, and develop optical metamaterials to control light propagation". These investigations will have the most direct relevance to technologies that rely on nonlinear light-matter interactions. These may includetechnologies for e.g., light generation, power limiting, upconversion-enabled imaging, analog image processing, quantum sensing, entangled photon pair generation, or quantum-state manipulation.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 10, 2025
- Source ID
- N000142512221
Entities
People
- Jon A Schuller
Organizations
- Office of Naval Research
- United States Navy
- University of California, Santa Barbara