Nonstandard applications of superconducting quantum interferometers: SQUIDS (Review)

Some applications of superconducting quantum interferometers are studied. The problems of quantum noise in the Josephson junction are discussed, theoretical estimates of their magnitude are given, and ways for achieving the limiting sensitivity of SQUIDs are indicated. Applications of SQUIDs in checking some basic physical laws (Newton's law, the principle of equivalence of inertial and gravitational masses, general relativity), in elementary particle physics (search for quarks and magnetic monopoles), in geophysics (magnetotelluric measurements, gradiometric measurements, gravimetric experiments, etc.), and in ultra-low-temperature physics (nuclear gyroscope, SQUIDs and NMR, ultra-low-temperature thermometry) are described. Both past and future experiments are studied and some further applications of SQUID-based magnetometers are indicated