Title :
Nuclear magnetic resonance with DC SQUID preamplifiers
Author :
Fan, N.Q. ; Heaney, Michael B. ; Clarke, John ; Newitt, D. ; Wald, Lawrence L. ; Hahn, Erwin L. ; Bielecki, A. ; Pines, A.
Author_Institution :
California Univ., Berkeley, CA, USA
fDate :
3/1/1989 12:00:00 AM
Abstract :
Describes five experiments illustrating the application of DC SQUID (superconducting quantum interference device) amplifiers to magnetic resonance experiments. The first experiment involved the observation of nuclear spin noise, that is the spontaneous emission of photons from an ensemble of 35Cl nuclei in the zero polarization state. The second experiment involved the use of the Q -spoiler in conventional NQR (nuclear quadrupole resonance) and NMR measurements in which one applies a large RF pulse to the nuclei to make them precess. The Q-spoiler was then used in an experiment to detect the oscillating electric polarization induced by 35Cl nuclear quadrupole moments. The fourth experiment involved the extension of the use of the Q-spoiler and SQUID amplifier to NMR, detecting the signal from 119Sn nuclei at 30 MHz. Finally, a SQUID amplifier was used with an untuned input circuit to detect the low-frequency NMR signal at 55 kHz from 195Pt nuclei in an applied field of 60 Gauss
Keywords :
SQUIDs; nuclear quadrupole resonance; preamplifiers; 30 MHz; 55 kHz; 119Sn nuclei; 35Cl nuclei; DC SQUID preamplifiers; NMR; Q-spoiler; magnetic resonance experiments; nuclear quadrupole resonance; nuclear spin noise; oscillating electric polarization; spontaneous emission; untuned input circuit; zero polarization state; Interference; Magnetic noise; Magnetic resonance; Nuclear magnetic resonance; Polarization; Preamplifiers; Pulse measurements; SQUIDs; Superconducting device noise; Superconducting devices;
Journal_Title :
Magnetics, IEEE Transactions on
