Measurement with a deployable quantum magnetometer

双谐振光抽运磁力计(DR-OPM)提供了一种强大而灵活的量子传感工具，应用于医疗保健、地磁学、制造业和基础物理。在过去的十年里，支撑科学和组件微制造的发展导致了在这些现实世界应用中产生影响的潜力大大增加。OPMS现在提供Femotesla磁场分辨率(地球磁场中十亿分之一的灵敏度)，在这种情况下，只有低温SQUID磁强计才能提供类似的性能。然而，紧凑、便携、无冷媒的OPM可用于许多SQUID磁力计的尺寸和成本令人望而却步的应用。OPMS将应用于医学研究和诊断的便携式心磁图和脑磁图，其可扩展性和外形因素为便携式传感器阵列带来了新的功能。在地磁测量中，相对于广泛使用的感应磁强计，OPM磁强计的本征校准是一个显著的优势，为测量、防御和导航提供了无校准测量。OPMS还可以配置为对亚兆赫频段的振荡磁场进行共振窄带检测，这得益于系统的频率不变限制量子噪声源，而不是广泛用于这些信号的经典约翰逊噪声限制感应式传感器。这种可调谐的检测模式是低场超极化核磁共振在制药和化工生产中的关键技术。DR-OPMS的灵敏度和精确度在网络基础物理搜索宇宙轴子和域壁方面也有重要的应用。该项目将专注于开发和演示DR-OPM配置，以最大限度地提高特定应用的性能。这将需要在实验室开发传感器模式和控制固件，目标是在优化的测试环境中以量子有限的精度工作，导致子系统优化并在现实世界应用中演示现场就绪的原型。该实验室的技术和系统组件的开发将推动与我们的最终用户网络合作设计和演示外地系统。这项工作将建立在我们在DR-OPM读数和反馈方案方面的专业知识以及在专业子系统设计方面的能力，包括紧凑型激光光学系统和微制碱蒸气电池。将提高子系统性能和准备就绪与DR-OPM操作中的新技术相结合，如数字自旋脉泽反馈方案，将这项研究置于关键的转换阶段。以实验室为基础的研究发展现在具有现场应用和快速影响的潜力。越来越高性能的设备的技术演示推动了终端用户兴趣的增加。该项目将利用这些机会，展示和加强量子传感器在磁学中的影响，并将成为正在进行的量子技术开发的组成部分。

Double-resonance optically pumped magnetometers (DR-OPMs) offer a powerful and flexible quantum sensing tool with applications in healthcare, geomagnetics, manufacturing and fundamental physics. The last decade has seen developments in the underpinning science and component microfabrication which result in greatly increased potential for impact in these real-world applications. OPMs now offer Femtotesla magnetic field resolution (part-per-billion sensitivity in Earth's field), a regime in which only cryogenic SQUID magnetometers offer comparable performance. However, compact, portable, cryogen-free OPMs can be used in many applications where the size and cost of SQUID magnetometers is prohibitive. OPMs will be applied to portable magneto-cardiography and magneto-encephalography for medical research and diagnosis, where their scalability and form factor unlock new capabilities for portable sensor arrays. In geomagnetic measurements the intrinsic calibration of OPM magnetometry against alkali atomic energy levels is a significant advantage over widely-used inductive magnetometers, offering calibration-free measurement for surveying, defence and navigation. OPMs can also be configured for resonant narrowband detection of oscillating magnetic fields in the sub-MHz band, benefiting from the system's frequency-invariant limiting quantum noise sources, rather than the classical Johnson-noise-limited inductive sensors widely used for these signals. This tuneable detection mode is a key technology for low-field hyperpolarised NMR in pharmaceutical and chemical manufacture. The sensitivity and accuracy of DR-OPMs also has important applications in networked fundamental physics searches for cosmological axions and domain walls. This project will focus on the development and demonstration of DR-OPM configurations tailored to maximise performance in specific applications. This will entail the development of sensor modes and control firmware in the laboratory, aiming to work at quantum-limited precision in an optimised test environment, leading on to sub-system optimisation and demonstration of field-ready prototypes in real-world applications. The development of techniques and system components in the lab will lead forward to the design and demonstration of field systems in collaboration with our network of end users. This work will build on our expertise in DR-OPM readout and feedback schemes and demonstrated capability in specialised subsystem design, including compact laser-optical systems and micro-fabricated alkali vapour cells. The combination of increasing subsystem performance and readiness with new techniques in DR-OPM operation, such as digital spin maser feedback schemes, places this research at a critical translational stage. Laboratory-based research developments now have potential for field application and rapid impact. Increasing end-user interest is driven by technology demonstration with increasingly high-performance devices. This project will exploit these opportunities, demonstrating and enhancing the impact of quantum sensors in magnetometry, and it will be an integral part of ongoing quantum technology development.