SBIR-STTR Award

Initial research and development towards a self-calibrated Rydberg-atom-based electric-field and power sensor for microwave and THz radiation is conducted. The sensor operates on atomic-physics and quantum-optics principles, especially electromagnetically induced transparency. Infrared and visual solid-state laser systems are employed to measure the energy levels of Rydberg atoms in room-temperature rubidium vapor cells exposed to the radiation. The observed level shifts and the applied field strength stand in a unique relation that only depends on invariable atomic parameters, not on technical calibration factors. In contrast to traditional instruments, this sensor is calibration-free and does not require an antenna. In the first task, the response of the sensor to strong radiation fields is quantitatively evaluated. The high-field response of the atoms is nonlinear and requires an advanced quantum-physics model known as Floquet theory. The performing company already uses such a model and will develop it further. In the second task, the sensors performance over a frequency range up to 250GHz is evaluated, and in the third task (Phase 1 option) solutions to the problem of atomic vapor-pressure variation are sought. The research includes the development of designs and concepts that will eventually lead to a portable prototype.

In EMC/EMI testing there is a demand for broadband (MHz to THz), self-calibrating, small, robust, and wide-dynamic-range detectors for electric fields up to about 10kV/m.Advanced field sensors are important in the expanding EMC/EMI testing industry, which serves aerospace, defense, automotive, telecommunications, safety, and security. Rydberg Technologies LLC (RT) is developing a new line of atom-based sensors that exploit the response of Rydberg atoms enclosed in small spectroscopic cells to the fields being measured. The atomic response is probed using a pair of laser beams routed to the cell via fiber-optics.In Phase II, RT will design and fabricate field probes that satisfy these described needs. The lasers, stabilization and data-processing components will be integrated into a control unit that connects via the fiber-optic cord to a robust, multi-range, light-weight field probe. The measurement system computes the RF electric field by matching the collected spectroscopic data with entries in a database of calculated spectra. A prototype measurement system will be demonstrated.In a Phase-II option and Phase III, the system will be integrated, made compact and ruggedized to realize a minimum viable product serving the ever-expanding needs of modern EMC/EMI testing.In EMC/EMI testing there is a demand for broadband (MHz to THz), self-calibrating, small, robust, and wide-dynamic-range detectors for electric fields up to about 10kV/m.Advanced field sensors are important in the expanding EMC/EMI testing industry, which serves aerospace, defense, automotive, telecommunications, safety, and security. Rydberg Technologies LLC (RT) is developing a new line of atom-based sensors that exploit the response of Rydberg atoms enclosed in small spectroscopic cells to the fields being measured. The atomic response is probed using a pair of laser beams routed to the cell via fiber-optics.In Phase II, RT will design and fabricate field probes that satisfy these described needs. The lasers, stabilization and data-processing components will be integrated into a control unit that connects via the fiber-optic cord to a robust, multi-range, light-weight field probe. The measurement system computes the RF electric field by matching the collected spectroscopic data with entries in a database of calculated spectra. A prototype measurement system will be demonstrated.In a Phase-II option and Phase III, the system will be integrated, made compact and ruggedized to realize a minimum viable product serving the ever-expanding needs of modern EMC/EMI testing. ---------- The fifth generation (5G) of mobile technologies will provide unprecedented improvements in connectivity, data speeds, latency, and bandwidth compared to existing 4G networks, enabling new military and commercial applications. In the military space, 5G will augment capabilities in intelligence, surveillance, and reconnaissance systems by addressing their growing demand for increased bandwidth and speed for information processing and dissemination, it will enable new approaches to and capability in command and control, including latency reduction in satellite communications, increased efficiency in military logistic and maintenance and similar high data capacity applications. Phased-array antennas are a major enabling technology to realize the potential of 5G and beyond. To address challenges in over-the-air (OTA) testing and measurement of phased array antennas for 5G, Rydberg Technologies will develop a near-field probe and imager based on Rydberg atom electromagnetic field measurement and imaging technology that exploits Rydberg atom vapors sensitive to millimeter-wave (MMW) fields from 28GHz to 300GHz. In this Phase II effort, Rydberg will prototype a broadband Rydberg-atom near-field probe and imager for high-resolution, speed, accuracy, and self-calibrated near-field measurements of MMW antennas for 5G and beyond. The Rydberg MMW imager will be comprised of a front-end with a vapor-cell imager probe and imaging system in a low-profile form factor for near-field measurements of antenna devices under test (DUTs). The front-end imager probe is connected to a back-end unit housing a laser, optics, and electronics package for readout from the atomic vapor of spatial MMW fields in the near-field of DUTs. Two-dimensional near-field images of MMW amplitude, phase, and polarization are rendered for near-field to far-field transformations. In Phase II the Rydberg MMW imager will reach a technology readiness level 5 with a performance evaluation to target metrics for field amplitude, phase, and polarization accuracy, spatial resolution, and speed. Near-field imaging of 5G antennas will be demonstrated.