Atomic sensors—devices that utilize individual atoms as the sensing mechanism—offer enormous prospects for high sensitivity, accuracy and immunity to environmental noise. This is because such sensors leverage quantum mechanical properties of the atom such as internal energy level splittings that do not change with time and are immune to sensor fabrication errors. While some of these sensors are now commercially available, they are still bulky instruments that must be individually assembled by hand and will not be widely disseminated in their current form. In this talk I will discuss a new architecture for quantum sensors based on miniaturized atomic beams, with applications to clocks, gyroscopes and photonic quantum devices.
Atomic sensors—devices that utilize individual atoms as the sensing mechanism—offer enormous prospects for high sensitivity, accuracy and immunity to environmental noise. This is because such sensors leverage quantum mechanical properties of the atom such as internal energy level splittings that do not change with time and are immune to sensor fabrication errors. While some of these sensors are now commercially available, they are still bulky instruments that must be individually assembled by hand and will not be widely disseminated in their current form. In this talk I will discuss a new architecture for quantum sensors based on miniaturized atomic beams, with applications to clocks, gyroscopes and photonic quantum devices.
Quantum sensing and measurement devices are reaching a new level of accuracy for high-precision measurements, allowing detection of the most minute changes in magnetic, electric, and strain fields, gravity, and time. In this talk, I will present an overview of how integrated photonic and nanophotonic devices utilize entanglement to improve measurement accuracy and sensitivity. Examples will include the development of ultrabright and ultra-efficient quantum light sources as resources for sensors, integrated photonic magnetometry with exquisite sensitivity that can be further enhanced with squeezing, and strain sensors based on optomechanical modulation of quantum emitters via surface acoustic wave resonators.
High-sensitivity sensors play a critical role in fundamental physics research, space magnetic field detection, geological monitoring, and biomedical applications. Atomic sensors, based on quantum mechanics principles, such as atomic magnetometers, atomic clocks, and atomic gyroscopes, etc. have emerged as pivotal technical equipment for precision measurements due to their exceptional sensitivity, low power consumption, and long-term stability. The atomic vapor cell, serving as the core component, facilitates quantum state manipulation via the Zeeman effect. Miniaturization and integration of these cells have not only advanced the development of portable atomic magnetometers but also provided a foundation for breakthroughs in chip-scale atomic clocks and enhanced navigation accuracy of atomic gyroscopes. The research progresses of chip-scale atomic vapor cells in recent years are reviewed. The advancements in alkali metal introduction methods, anti-relaxation surface coatings, and micro-nano fabrication techniques have enabled the miniaturization of atomic vapor cells while preserving high performance, creating new opportunities for the deployment of quantum sensing technologies across diverse fields. Looking ahead, multifunctional integration and material innovations in atomic vapor cells are expected to further broaden their applications in time-frequency standards, inertial navigation systems, and weak magnetic field measurements.
Atomic clocks are an important part of many potential quantum sensors, in addition to constituting a type of quantum sensor in their own right. For many applications, high-performance clocks must be realized in a manner compatible with operation outside of a laboratory. In this talk, I will outline efforts at developing the integrated photonics technology needed to miniaturize optical atomic clocks, including our lab’s own efforts on nonlinear nanophotonics components. I will also discuss how such integrated photonics can also impact the development of other types of quantum sensors, and present some of the challenges involved in advancing these technologies.
Chip-scale atomic devices combine elements of precision atomic spectroscopy, silicon micromachining, and advanced diode laser technology to create compact, low-power, and manufacturable instruments with high precision and stability. Microfabricated alkali vapor cells are at the heart of most of these technologies, and the fabrication of these cells is discussed in detail. We review the design, fabrication, and performance of chip-scale atomic clocks, magnetometers, and gyroscopes and discuss many applications in which these novel instruments are being used. Finally, we present prospects for future generations of miniaturized devices, such as photonically integrated systems and manufacturable devices, which may enable embedded absolute measurement of a broad range of physical quantities.
The discrete electronic energy levels in atoms and the ability to probe and control them using their interactions with electromagnetic fields have enabled a host of applications in quantum sensing and metrology, including atom-based time and frequency standards, magnetometers, and inertial sensors. Precision measurements with atoms rely on the capability to control the frequency, phase, polarization, and direction of photons used to prepare and measure quantum systems, and thus developments in near-infrared optics and photonics are critical to advancing state-of-the-art atomic sensors. In this talk, I will summarize the basic principles of atom-based quantum sensing and highlight the role of atom-photon interactions in quantum measurements. The benefits and challenges of realizing atom-based quantum sensors will be illustrated through examples from my prior research, including the development of sensitive accelerometers and gyroscopes based on cold-atom interferometers. I will discuss the critical developments in photonic engineering that are still needed to improve the performance and functionality of atom-based-quantum sensors and our research progress at UW-Madison towards addressing these needs.
We report on progress in the characterization of systematic shifts in chip-scale atomic beam clocks, which offer the potential for improved long-term stability relative to existing chip-scale atomic clocks. Previous work has demonstrated the key features of chip-scale atomic beam devices including the use of a microfabricated Si/glass atomic beam cell, passively maintained vacuum environment, and an integrated Rb atomic beam source. A beam clock has been realized using Ramsey coherent population trapping interrogation with a demonstrated short-term fractional frequency stability of ≈ 1.2 × 10^(-9)at 1 s of integration. In this talk, we discuss the path toward long-term stabilty in chip-scale atomic beam clocks and leading clock systematics. Chip-scale atomic beams are a new platform for quantum sensing which offer the potential for long-term stability in compact, low-power applications.