Travelling-wave nuclear magnetic resonance
- 1 February 2009
- journal article
- Published by Springer Science and Business Media LLC in Nature
- Vol. 457 (7232), 994-998
- https://doi.org/10.1038/nature07752
Abstract
Nuclear magnetic resonance (NMR) is one of the most versatile experimental methods in chemistry, physics and biology, providing insight into the structure and dynamics of matter at the molecular scale. Its imaging variant-magnetic resonance imaging (MRI)-is widely used to examine the anatomy, physiology and metabolism of the human body. NMR signal detection is traditionally based on Faraday induction in one or multiple radio-frequency resonators that are brought into close proximity with the sample. Alternative principles involving structured-material flux guides, superconducting quantum interference devices, atomic magnetometers, Hall probes or magnetoresistive elements have been explored. However, a common feature of all NMR implementations until now is that they rely on close coupling between the detector and the object under investigation. Here we show that NMR can also be excited and detected by long-range interaction, relying on travelling radio-frequency waves sent and received by an antenna. One benefit of this approach is more uniform coverage of samples that are larger than the wavelength of the NMR signal-an important current issue in MRI of humans at very high magnetic fields. By allowing a significant distance between the probe and the sample, travelling-wave interaction also introduces new possibilities in the design of NMR experiments and systems.Keywords
This publication has 24 references indexed in Scilit:
- Remote detection of nuclear magnetic resonance with an anisotropic magnetoresistive sensorProceedings of the National Academy of Sciences of the United States of America, 2008
- Safety of human MRI at static fields above the FDA 8T guideline: Sodium imaging at 9.4T does not affect vital signs or cognitive abilityJournal of Magnetic Resonance Imaging, 2007
- Engineering and design concepts for quasioptical high‐field electron paramagnetic resonanceConcepts in Magnetic Resonance Part B, 2004
- Microstructured Magnetic Materials for RF Flux Guides in Magnetic Resonance ImagingScience, 2001
- High frequency volume coils for clinical NMR imaging and spectroscopyMagnetic Resonance in Medicine, 1994
- Cylindrical coils near self‐resonanceMagnetic Resonance in Medicine, 1993
- Detection of NMR Using a Josephson-Junction MagnetometerPhysical Review Letters, 1972
- Observation of a Photon EchoPhysical Review Letters, 1964
- Nuclear Induction Due to Free Larmor PrecessionPhysical Review B, 1950
- Resonance Absorption by Nuclear Magnetic Moments in a SolidPhysical Review B, 1946