Collaborative Research: First-Principle Control of Novel Resonances in Non-Hermitian Photonic Media

非技术描述：该NSF奖支持一项综合研究、教育和推广项目，重点研究光在固体材料中的新行为。长期以来，光学科学一直在追求操纵光和其他不可见波（如红外光和微波）的各种特性的能力。传统的例子包括用镜子和透镜弯曲光线，用激光和led发光。该项目采用了一种独特的方法，深入探索光学材料的活性特性，特别是它们对光的衰减或放大的适应性，如何深刻地改变它们与环境的相互作用。这方面，在过去已经得到了有限的研究，提出了一个引人注目的途径，以新的方式理解和利用光的动态行为。这项研究的结果有望提供一种新型的光-物质相互作用，从而推进我们对光学、物理学、材料科学和光电子学的基本理解。此外，通过引入光如何感知其环境的新范式，该项目旨在显著增强光通信和计算中使用的光子器件的功能。这包括开发一种超宽带可调谐激光器，能够实现超过当前最先进技术的波长调谐范围，超过一个数量级。这些进步对各行各业和我们的日常生活都有着深远的影响。利用纽约城市大学（美国最大的城市大学系统）和宾夕法尼亚大学（全国教育创新的领导者）的资源，研究人员将与多个外展单位合作，提高纽约市和大费城地区K-12学生对现代光学和光子学的认识和兴趣。这个跨学科项目还为研究生、本科生和高中生提供了宝贵的研究机会，重点是招募和指导来自STEM中代表性不足群体的学生。技术描述：传统上，光与物质之间的相互作用发生在振荡电磁场与带电粒子共振时，例如电介质中的偶极子。这种相互作用可以用耦合振荡器来模拟，其中被动光子模式代表由物质折射率的实部定义的电磁环境。根据物质和光子模式之间的耦合强度，通常定义了两种类型的光-物质相互作用。然而，这些定义忽略了物质的一个重要方面：物质折射率的虚部，即光学增益和损耗，这可以显著影响它们的相互作用。在这个合作项目中，主要研究者的目标是通过对折射率虚部的第一性原理控制来建立一个复杂的非厄米光子环境。结果展示了一种新型的光-物质相互作用，它完全由系统的非厄米性控制，由以前未探索的光子有源共振引起。该项目结合了综合理论和实验研究，通过在III-V半导体平台上的战略波导模式工程来设计光子有源谐振器，以揭示其独特的特性，并进一步利用它们来开发具有超宽带可调性的鲁棒本征单模激光。这些进步将为用于光通信和计算的新一代集成光子器件奠定基础。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Nontechnical description: This NSF award supports an integrated research, education, and outreach project that focuses on studying a novel behavior of light within solid materials. Optical science has long pursued the ability to manipulate various properties of light and other invisible waves, such as infrared light and microwaves. Traditional examples include bending light with mirrors and lenses and generating light with lasers and LEDs. This project adopts a unique approach by delving into the exploration of how the active property of optical materials, specifically their suitability for attenuation or amplification of light, can profoundly transform their interactions with the environment. This aspect, which has received limited investigation in the past, presents a compelling avenue for understanding and harnessing the dynamic behavior of light in novel ways. The outcomes of this investigation are expected to deliver a new type of light-matter interaction, thereby advancing our fundamental understanding of optics, physics, materials science, and optoelectronics. Moreover, by introducing a novel paradigm for how light perceives its environment, the project aims to significantly enhance the functionality of photonic devices used in optical communications and computing. This includes the development of an ultra-broadband tunable laser capable of achieving a wavelength tuning range surpassing the current state-of-the-art, by more than one order of magnitude. These advancements have far-reaching implications across industries and in our daily lives. Leveraging the resources of the City University of New York, the largest urban university system in the US, and the University of Pennsylvania, a national leader in education innovation, the researchers will collaborate with multiple outreach units to increase awareness and interest in modern optics and photonics among K-12 students in New York City and the greater Philadelphia area. This interdisciplinary project also provides valuable research opportunities for graduate, undergraduate, and advanced high-school students, with a focus on recruiting and mentoring students from underrepresented groups in STEM.Technical description: Traditionally, the interaction between light and matter occurs when an oscillating electromagnetic field resonantly engages with charged particles, such as dipoles in dielectrics. This interaction can be modeled using coupled oscillators, where the passive photonic modes represent the electromagnetic environment defined by the real part of the matter's refractive index. Two types of light-matter interactions are typically defined based on the coupling strength between matter and photonic modes. However, these definitions overlook an important aspect of matter: the imaginary part of the matter’s refractive index, i.e., optical gain and loss, which can significantly impact their interactions. In this collaborative project, the principal investigators aim to establish a complex non-Hermitian photonic environment through first-principle control of the imaginary part of the refractive index. The results showcase a novel type of light-matter interaction that is exclusively governed by the system's non-Hermiticity, arising from previously unexplored photonic active resonances. The project combines integrated theoretical and experimental research to design photonic active resonators through strategic waveguide mode engineering on the III-V semiconductor platform to unravel their unique properties and further leverage them for the development of robust intrinsic single-mode lasing with an ultra-broadband tunability. These advancements will lay the groundwork for a new generation of integrated photonic devices for optical communication and computing.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.