Next-Generation Readout Electronics for nEDM

Ultra-sensitive Superconducting Quantum Interference Device (SQUID) sensors are the most sensitive detectors of magnetic flux available. Such SQUID-based sensor systems are critical components of key experiments in nuclear physics, including the search for the neutron electric dipole moment (nEDM) being carried out by Los Alamos National Laboratory and collaborators at several other research institutions. However, currently available SQUID readout electronics are extremely dated in terms of component availability, design, and ultimate performance, as well as data acquisition and computer interface options. For these reasons, it is questionable as to whether or not these readout electronics will be suitable or even available to read out the SQUID sensors that will be required for the nEDM experiment. This project describes a next-generation, flux-modulation-based SQUID readout that features a novel, modular design. The design will provide excellent flexibility for a wide variety of multi-channel applications, with optional battery operation and optical isolation to ensure the highest possible noise immunity. Precision, low-drift components in key parts of the analog feedback circuit will ensure the necessary stability for long-term measurements. Stand-alone control software will simplify set-up and operation, including automatic calibration and tuning. Commercial Applications and other Benefits as described by the awardee: State-of-the-art SQUID readout electronics should have applications in biomedical imaging (e.g., magnetoencephalography and magnetocardiography), geophysical exploration (e.g., surveys for oil and mineral exploration), and non-destructive testing of materials (e.g., the detection of impurities and contaminants in food, integrated circuit fault analysis, and magnetic microscopic imaging).