QuSeC-TAQS: Quantum Atomic Coherence-based Charged Particle Sensor

这个跨学科的项目将实施和测试一种新的方法来检测带电粒子束（例如，电子束）使用基于具有激光和微波的原子光谱的量子感测方案。所提出的方法将通过非侵入式光学观测提供关于光束强度、位置、宽度、轮廓和方向的信息。通过这种方式，可以连续监测粒子束，而不会中断或干扰。这种方法对于核加速器中的高功率和高电流粒子束特别有用，其中由于在线检测器吸收的高功率，任何侵入性监测变得困难。所提出的新量子传感器的基本思想是通过将“检测器”原子定位在带电粒子附近，通过它们的磁场或电场来检测带电粒子。由于这些场，这些原子的能级将发生变化，然后可以使用激光或微波探针进行测量。该项目将使用两种形式的铷原子作为探测介质：（1）室温下的热原子和（2）微开尔文温度下的超冷原子。研究生和本科生以及博士后研究员将接受原子物理学，光学和量子科学技术以及粒子束物理学的培训，为量子信息科学的劳动力做准备。该项目还将为公众和中学生开展量子科学方面的外联活动。这个跨学科项目是威廉玛丽学院的量子物理学家、托马斯杰斐逊国家加速器设施的核物理学家和MITRE公司的研究人员之间的合作努力。更广泛地说，带电粒子的探测在科学和工程的许多领域都有广泛的应用，从加速器和等离子体设施到国防和空间科学。更具体地说，电子束产生的磁场将主要影响基态原子的自旋量子态，而电场将扰动原子的高激发里德堡态。这些扰动可以通过激光场的光学性质（透射率、偏振方向）的变化来检测，以重建电子束的性质。该项目将包括三项主要任务。在第一项任务中，该团队将使用近室温热铷原子来描绘电子束，以开发和优化用于核物理的实用束诊断设备。在第二项任务中，该团队将建造一个超冷原子装置，该装置将使用微波拉姆齐干涉结合里德伯激发来描绘电子束。这种无背景的方法预计将具有高灵敏度，并有可能用于检测单电子轨道。最后，在第三项任务中，该项目将研究使用非经典光学探针（如压缩光）进一步提高探测灵敏度，使其超过量子标准极限。该奖项反映了NSF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。

This interdisciplinary project will implement and test a new approach for detecting charged particles beams (e.g., an electron beam) using quantum sensing schemes based on atomic spectroscopy with lasers and microwaves. The proposed method will provide information about the beam strength, position, width, profile, and direction via non-invasive optical observations. This way, a particle beam can be continuously monitored without interruptions or disturbances. This approach is particularly useful for high power and high current particle beams in nuclear accelerators, in which any invasive monitoring becomes difficult due to the high power absorbed by an in-line detector. The basic idea of the proposed new quantum sensor is to detect charged particles via their magnetic or electric field by positioning “detector” atoms in proximity of the charged particles. Such atoms will experience a shift in their energy levels due to these fields, which can then be measured using a laser or microwave probe. The project will use rubidium atoms in two forms as the detection medium: (1) thermal atoms at room temperature and (2) ultracold atoms at micro-Kelvin temperatures. Graduate and undergraduate students, as well as a postdoctoral researcher, will be trained in atomic physics, optics, and quantum science techniques, as well as particle beam physics, in preparation for the quantum information science workforce. The project will also conduct outreach activities in quantum science for the public and secondary school students. This interdisciplinary project is a collaborative effort between quantum physicists at the College of William & Mary, nuclear physicists at the Thomas Jefferson National Accelerator Facility, and researchers at MITRE Corporation. More broadly, the detection of charged particles has broad applications across many areas of science and engineering, from accelerator and plasma facilities to defense and space science.More specifically, the electron-beam generated magnetic field will primarily affect the spin quantum state of ground state atoms, while the electric field will perturb the highly excited Rydberg state of atoms. These perturbations can be detected via changes in the optical properties (transmission, polarization direction) of a laser field to reconstruct the properties of the electron beam. The project will consist of three main tasks. In the first task, this team will employ near-room temperature thermal rubidium atoms to profile an electron beam to develop and optimize a practical beam diagnostic device for nuclear physics. In a second task, this team will construct an ultracold atom apparatus that will profile an electron beam using microwave Ramsey interference in combination with Rydberg excitation. This background-free approach is expected to have high sensitivity and has the potential for detecting single electron tracks. Finally, in a third task, the project will investigate the use of non-classical optical probes (such as squeezed light) to further improve the detection sensitivity beyond the quantum standard limit.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.