EAGER: Fundamental Considerations in Using Non-Hermitian Microscale Resonant Optical Structures for Rotation Sensing

测量旋转速率在许多现有和新兴的科学和技术领域中至关重要，从广义相对论到机器人技术，医学成像，虚拟现实，计算机游戏，无人驾驶飞行器（无人机）和无人驾驶汽车。多年来，各种物理现象已被用于测量旋转速率。在光学中，Sagnac效应已被用于开发一些用于确定旋转速度的最精细和最精确的工具。事实上，到目前为止，自由空间环形激光陀螺仪（RLG）和无源光纤陀螺仪是迄今为止最灵敏的旋转传感器之一。然而，尽管环形激光陀螺仪在对冲击和振动的弹性方面具有上级性能，但是环形激光陀螺仪不容易扩展，因此不能集成在芯片上。最近，一种基于差分增益结构的技术被提出来显著提高RLG的灵敏度。所提出的努力的目标是调查这种技术的基本限制，并铺平了道路，对超灵敏的环形激光陀螺仪芯片上的发展。最近的研究表明，非厄米简并可以显著提高光子谐振结构的灵敏度。这种灵敏度增强可以变得非常有用的一个领域是环形激光陀螺仪（RLG）。在标准光学陀螺仪中，灵敏度随着封闭面积的平方根而增加。这种行为导致了尺寸和灵敏度之间的基本权衡。然而，使用非厄米简并或特殊点的灵敏度增强提出了几个基本问题，量子噪声，检测限，测量稳定性和信噪比。该提案旨在以分析和结论性的方式解决这些问题，并确定非厄米陀螺仪的性能指标。此外，陀螺仪的一些组成部分的设计和制造将被考虑。这项研究不仅可能会影响芯片级陀螺仪的技术，而且还将推动非厄米物理学的发展。

Measuring rotation rate is of utmost importance in a number of existing and emerging areas of science and technology, from general relativity, to robotics, medical-imaging, virtual reality, computer games, unmanned aerial vehicles (drones), and driverless cars. Over the years, various physical phenomena have been utilized for measuring rotation rates. In optics, the Sagnac effect has been employed to develop some of the finest and most accurate tools for determining rotational speeds. In fact, as of now, free-space ring laser gyroscopes (RLG) and passive fiber optic gyroscopes are among the most sensitive rotational sensors built to date. However, despite their superior performance in terms of resilience to shock and vibration, ring laser gyroscopes are not readily scalable and therefore cannot be integrated on chip. Recently, a technique based on differential gain architecture was proposed to significantly increase the sensitivity of RLGs. The goal of the proposed effort is to investigate the fundamental limitations of this technique and to pave the way towards the development of ultrasensitive ring laser gyroscopes on chip. The project will provide scientific training for students.Recent studies suggest that non-Hermitian degeneracies can significantly enhance the sensitivity of photonic resonant structures. One area where such sensitivity enhancement can become very useful is in ring laser gyroscopes (RLGs). In standard optical gyroscopes, sensitivity increases with the square root of the enclosed area. This behavior results in a fundamental trade-off between size and sensitivity. However, the use of non-Hermitian degeneracies or exceptional points for sensitivity enhancement raises several fundamental questions in terms of quantum noise, detection limit, measurement stability, and signal to noise ratio. The proposal aims to address these issues in an analytical and conclusive way and to determine the performance metrics for non-Hermitian gyroscopes. In addition, the design and fabrication of some of the constituent parts of the gyroscope will be considered. The proposed research may not only impact the technology of chip-scale gyroscopes, but will also advance the science of non-Hermitian physics.