PM: Optomechanical Dark Matter Detectors

暗物质的起源是我们这个时代永恒的科学谜团之一。经过40年的探索，直接探测到暗物质“粒子”仍然难以捉摸，这促使人们对搜索空间和探测策略进行全面的重新思考。光机械传感器，利用光来探测固态物体的微小变形，已经出现在最前沿，因为它们提供了大量的暗物质候选物质，这些候选物质与原子的大小或位置有关。该项目的目的是建立第一代光力学暗物质探测器，利用近年来使光力学系统能够在量子极限下运行的技术。除了基础物理学之外，该项目还将解决量子传感器发展的关键挑战，如可扩展性和退相干缓解。一个更广泛的目标是培养对粒子和量子物理有混合兴趣的新一代研究生和博士后，认识到未来的量子劳动力将受益于广泛的科学背景。具体来说，该项目将联合实验家（PI）和理论合作者，探索使用一系列低温光机械加速度计探测超轻“暗光子”暗物质。每个加速度计都是基于一个频率可调，超高q氮化硅膜耦合到一个光学腔。氮化硅膜是一种成熟的机械谐振器技术，在毫开尔文温度下具有极低的耗散，可以在声频下获得皮克加速度灵敏度。在这个项目的探索阶段，将在4 K低温恒温器中开发一个基于单厘米尺度膜的原型探测器。目标将是超越目前对暗物质光子的限制。E-9比1。e-11 eV质量（1khz - 100khz康普顿频率）范围由Eöt-Wash扭平衡设定实验。长期的努力，包括在标准量子极限下探测光子晶体膜阵列，将以数量级的改进为目标，并提供各种基本弱力测试。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。

The origin of dark matter is one of the enduring scientific mysteries of our time. After four decades of searching, direct detection of a dark matter “particle” remains elusive, spurring calls for a comprehensive rethinking of the search space and detection strategy. Optomechanical sensors, which use light to probe minute deformations of solid-state objects, have emerged at the forefront, as they give access to a broad set of dark matter candidates which couple to the size or position of atoms. The aim of this project is to build a first generation optomechanical dark matter detector, drawing on techniques which have enabled optomechanical systems to operate at the quantum limit in recent years. Beyond fundamental physics, the project will address key challenges to the development of quantum sensors, such as scalability and decoherence mitigation. A broader goal is the education of a new generation of graduate students and postdocs with hybrid interests in particle and quantum physics, recognizing that the future quantum workforce will benefit from drawing upon a wide pool of scientific backgrounds.Specifically, the project will join experimentalists (the PI) and theory collaborators to explore detection of ultralight “dark photon” dark matter using an array of cryogenic optomechanical accelerometers. Each accelerometer is based on a frequency-tunable, ultra-high-Q silicon nitride membrane coupled to an optical cavity. Silicon nitride membranes are a well-established mechanical resonator technology and can have exceptionally low dissipation at millikelvin temperatures, giving access to pico-g acceleration sensitivities at acoustic frequencies. In this exploratory phase of the project, a prototype detector will be developed based on a single centimeter-scale membrane in a 4 K cryostat. The goal will be to eclipsing current constraints on dark photon dark matter in the 1.e-9 to 1.e-11 eV mass (1 kHz – 100 kHz Compton frequency) range set by the Eöt-Wash torsion balance experiments. Longer term efforts, involving an array of photonic crystal membranes probed at the standard quantum limit, will target order of magnitude improvement and give access to a variety of fundamental weak force tests.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.