Geometrically-differential NMR in a stripline front-end

Abstract

A major challenge facing the development of portable, low-cost NMR is the development of robust yet sensitive transceivers, for which several trade-offs in scalability, performance and complexity are usually necessary. Here we report on a stripline-based NMR detector that overcomes previous limitations. It features a sensitivity of 5.7×10-4 TA−1Ω−0.5 over a sample volume of 10 mm × 10 mm × 3 mm, an exceptionally high B1 homogeneity of A450/A90=98.4%, intrinsic electromagnetic shielding of 27 dB from environmental influences, and a total signal gain of 68 dB in the presence of a noise factor of 1.28, without any exterior shielding. The new dual-coil arrangement offers a downscalable geometry optimised for gap magnets, and it is voltage-tunable and plug-in compatible with commercial software-defined radio spectrometer boards. Exceptionally, it features both common-mode and novel differential-mode NMR measurement abilities.