Sensitive SQUID-Based Detectors of the Magnetization of Polarized Nuclei

75308S Fundamental research in nuclear physics, such as the search for the neutron electric dipole moment (EDM), requires advances in detector systems and instrumentation. In particular, advanced detector systems are needed to enable precision measurements of the magnetization of polarized nuclei in noisy environments. This project will develop a novel magnetic detector system, based on ultra-sensitive superconducting quantum interference device (SQUID) sensors, that is sensitive to magnetic field gradients and discriminates against uniform magnetic fields and ambient noise sources. During Phase I, three prototype detector designs were developed, fabricated, and tested. The third design met the key technical goals and was shown to be operable in a typical laboratory environment with very low-noise performance. In addition, the design of suitable packaging for the detectors was completed and the first package assemblies were built. In Phase II, STAR further design improvements will enhance detector performance by a factor of two, and an existing detector fabrication process will be transitioned from 100-mm wafers to 150-mm wafers, significantly reducing detector costs. Commercial Applications and Other Benefits as described by the awardee: The advanced superconducting quantum interference device magnetic detectors, with high ambient noise rejection and low cost, will be attractive for commercial biomedical imaging applications such as magnetocardiography. The integrated thin-film detector design should provide a more cost effective solution with greater manufacturability, compared to conventional designs that require a substantial amount of hand assembly and adjustment.