Low-frequency vector electrometry with a Rydberg dipolar chain. Credit: Higher Education Press Measuring low-frequency electric fields with high precision is still a major scientific challenge. Existing sensing technologies often fall short when trying to achieve three key goals at once: accurate calibration, compact size, and the ability to determine both the strength and direction of a field. Rydberg atoms have emerged as a promising solution in the field of quantum metrology. These atoms are