Low-field magnetic resonance imaging with a high-T-c dc superconducting quantum interference device

A spectrometer incorporating a high transition temperature dc superconducti ng quantum interference device (SQUID) is used to obtain nuclear magnetic r esonance signals from protons in mineral oil at room temperature in fields up to 3 mT. The spatial separation between the SQUID magnetometer at 77 K a nd the sample at room temperature is less than 1 mm. At 2 mT, the signal is easily resolved in a single scan. Two-dimensional images of samples consis ting of pieces of lucite or glass immersed in mineral oil are obtained at 2 mT. (C) 1999 American Institute of Physics. [S0003-6951(99)03649-9].