I-Corps: Atomic High Magnetic Field Sensors

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

The pursued technology is based on a measurement approach that utilizes vapor cells containing atoms in highly excited states (Rydberg states) that function as sensors for strong magnetic fields. Key features of the atomic high magnetic field sensor are: (1) since the invariable response of atoms is used for the field detection, the operation of these sensors is intrinsically calibration- and drift-free, (2) the sensors exhibit high precision and a large measurement range, (3) metallic components that may be problematic with sensing magnetic fields are not present in the sensor head (all-optical signal readout), (4) the sensors have high-spatial-resolution imaging capability, and (5) the sensors are immune to electromagnetic interference (EMI) effects. High magnetic fields in the range of 1-100 Tesla are becoming increasingly important in science and engineering settings. There is growing demand for such fields at university laboratories and government-funded research facilities around the world, and for use in improved industrial processing techniques. In medicine, strong magnets continue to drive improvements in magnetic resonance imaging (MRI) products and systems. Advances in high-magnetic-field science and applications continue to benefit directly from improvements in the detection and control of strong magnetic fields, driving demand for devices capable of sensing and measurement in different high-magnetic-field environments with ever-more stringent requirements on the device?s performance capabilities. It is planned to develop a high-magnetic-field sensor with a sensor head that is electrode-free, metal-free, and based on atomic spectroscopy. The response of the Rydberg atoms to the fields to be measured is detected using electromagnetically induced transparency (EIT), a quantum-optics method that allows all-optical measurements of Rydberg energy levels without need for vacuum systems and particle detectors. Much of the infrastructure required for measuring strong magnetic fields using Rydberg-atom EIT (lasers, electronics, data acquisition and processing) is already present in the laboratory from previous work. The team has already prepared a setup consisting of strong permanent magnets (field about one Tesla) surrounding the spectroscopic cell. The testing will include the useful field range, the resolution and accuracy, and the detection bandwidth. It is planned to perform one or two test runs within a strong superconducting magnet that can provide 6 to 9 Tesla of magnetic field. The team believes that the sensor technology to be developed can have distinct competitive advantages over current sensors on the market. The potential contribution of the work to science, scientific applications and eventually to the market is the development of atomic sensors for strong-magnetic-field measurement and imaging applications, with performance characteristics that address limitations of existing high-magnetic-field sensor and measurement technologies. The potential customers include national laboratories with high-magnetic-field capabilities and detection needs, such as particle colliders, plasma physics labs, and the National High Magnetic Field Lab, industrial materials manufacturers, medical MRI research and development centers, and electromagnetic compliance (EMC)/EMI testing laboratories in the aerospace, automotive, and defense industries.