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

Abstract
A spectrometer incorporating a high transition temperature dc superconducting quantum interference device (SQUID) is used to obtain nuclear magnetic resonance 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 and 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 consisting of pieces of lucite or glass immersed in mineral oil are obtained at 2 mT.