Rydberg Atoms Achieve Non-Invasive Subwavelength Microwave Imaging of Reactive Near-Fields

Accurate mapping of microwave fields is crucial for advances in diverse fields including aerospace engineering, medical imaging, and the testing of integrated circuits. Chaoyang Hu, Mingyong Jing, and Zongkai Liu, along with their colleagues, now present a groundbreaking method for achieving this, overcoming the limitations of traditional metal probes which inevitably distort the very fields they aim to measure. The team demonstrates, for the first time, subwavelength imaging of these reactive near fields using Rydberg atoms as a non-invasive probe, engineered to minimise disturbance to the measured signal. This innovative approach achieves exceptional imaging resolution and produces field distributions that closely match complex simulations, confirming its accuracy and genuinely non-invasive character, and opens new possibilities for applications requiring precise, undisturbed measurements, such as detecting defects in microchips.

The study established a non-invasive technique for mapping reactive near fields, crucial for applications like aerospace engineering and integrated-circuit diagnostics, where even minor disturbances can compromise accuracy. Researchers engineered a compact, fibre-integrated Rydberg probe designed to minimize field perturbation, a significant advancement over traditional metal probes which act as strong scatterers and distort the measured fields. The experimental setup involved illuminating test structures, including horn and chip antennas and deeply subwavelength metallic tags, with microwaves while simultaneously scanning the Rydberg probe across the near-field region.

This probe leverages the unique properties of Rydberg atoms to detect microwave fields without significantly altering them, enabling accurate measurements of the undisturbed field distribution. The system achieves an imaging resolution of 8mm, and independent measurements demonstrate an ultimate spatial resolution of 0.62mm, corresponding to λ/56 at the operating wavelength, significantly exceeding the capabilities of conventional probes.,.

Rydberg Atoms Resolve Subwavelength Microwave Fields

Scientists have achieved a breakthrough in microwave imaging by demonstrating subwavelength resolution using a novel Rydberg atom-based probe, fundamentally advancing the field of non-invasive field mapping. This work establishes a practical route toward applying Rydberg-atom-based quantum technology to reactive near-field microwave subwavelength imaging, with particular promise for non-invasive diagnostics of microwave components and integrated circuits. The team engineered a fibre-integrated Rydberg probe, entirely free of metal near the sensing volume, to minimize field perturbation and enable accurate mapping of microwave fields without disturbing them. Experiments revealed an imaging resolution of λ/56, demonstrating the probe’s ability to resolve features much smaller than the wavelength of the microwave radiation.

Measurements of field distributions achieved structural similarity approaching unity when compared with full-wave simulations, confirming both the subwavelength spatial resolution and the genuinely non-invasive character of the probe. This level of accuracy surpasses conventional metal-based probes, which inevitably perturb the fields they measure due to induced currents and secondary radiation. The research team constructed a three-dimensional imaging platform incorporating the Rydberg probe, a robotic arm for precise positioning, and a dedicated optical detection and reconstruction algorithm. Using this system, scientists successfully imaged the reactive near field generated by both a standard gain horn antenna and an ultra-wideband chip antenna, both driven at 8.,.

Rydberg Atoms Map Microwave Fields Non-Invasively

This research demonstrates a new method for imaging microwave fields using Rydberg atoms, offering a non-invasive approach to mapping these fields at a subwavelength scale. The team successfully resolved the detailed structure of fields generated by both horn and chip antennas, achieving a high degree of accuracy when compared with full-wave simulations. Importantly, the Rydberg atom probe minimally disturbs the measured fields, unlike conventional metal probes which significantly alter the field distribution. This non-invasive character allows for accurate measurements even in scenarios where small perturbations would obscure the underlying physics.

The achieved spatial resolution, approximately 0.62 millimetres, represents a substantial advancement in near-field imaging capabilities. This level of detail enables the recovery of information inaccessible to traditional metal sensors, opening new possibilities for applications such as integrated circuit testing and antenna characterization. While current work focuses on amplitude mapping, the authors acknowledge limitations in data acquisition speed and the need for further miniaturization. Future research will concentrate on improving these aspects, alongside the development of vector and phase-resolved measurements, and exploring potential on-chip photonic integration to enhance the system’s capabilities and broaden its application space.,.

Rydberg Atoms Map Subwavelength Microwave Fields

Scientists have pioneered a new method for imaging microwave fields at a subwavelength scale using Rydberg atoms, overcoming limitations of traditional metal probes. The study establishes a non-invasive technique for mapping reactive near fields, crucial for applications in aerospace engineering and integrated-circuit diagnostics, where even minor disturbances can compromise accuracy. Researchers engineered a compact, fibre-integrated Rydberg probe designed to minimize field perturbation, a significant advancement over metal probes which distort measured fields. The experimental setup involved illuminating test structures, including antennas and subwavelength tags, with microwaves while scanning the Rydberg probe across the near-field region.

This probe leverages the unique properties of Rydberg atoms to detect microwave fields without altering them, enabling accurate measurements of the undisturbed field distribution. The system achieves an imaging resolution of 8mm, with independent measurements demonstrating an ultimate spatial resolution of 0.62mm, corresponding to λ/56 at the operating wavelength, significantly exceeding the capabilities of conventional probes.