Synopsis: Breathe In, Breathe Out

Advances in magnetic resonance spectroscopy could remedy the problems caused by movement or unstable fields during a scan.
Synopsis figure
Courtesy S. Chinthalapalli/Indian Institute of Technology

In an NMR measurement, strong and stable magnetic fields are needed to accurately determine the resonant frequencies of nuclear spins. However, sample instabilities and inhomogeneities often cause fluctuations in local fields, which is problematic for high-resolution spectroscopy. Moreover, the highest available magnetic fields can only be generated by pulsed schemes with poorer spatiotemporal stability than that found in persistent superconducting magnets. Now, in a paper in Physical Review Letters, Srinivas Chinthalapalli at the Indian Institute of Technology, New Delhi, and collaborators address this issue with a novel multidimensional NMR method called long-lived-coherence correlation spectroscopy (LLC-COSY) that acquires ultrahigh resolution NMR spectra in highly inhomogeneous or unstable fields.

LLC-COSY relies on coherent superpositions of spin states with very long lifetimes and hence very narrow linewidths. The authors’ method is insensitive to inhomogeneous broadening effects, including those due to local magnetic field fluctuations, and can reduce homogeneous broadening by almost an order of magnitude.

Breathing lungs, pulsating arteries, and surgical implants are among the unstable biological objects amenable to LLC-COSY investigations. LLC-COSY may also enable the use of the highest-field pulsed magnets for high-resolution NMR, opening unexplored frontiers to NMR research. – Matteo Rini


More Features »


More Announcements »

Subject Areas

MagnetismBiological PhysicsMedical Physics

Previous Synopsis

Nuclear Physics

Neutron Knockout

Read More »

Next Synopsis

Related Articles

Synopsis: Explaining Grid-Cell Firing
Biological Physics

Synopsis: Explaining Grid-Cell Firing

A model explains why grid cells—neurons that are part of the brain’s positioning system—fire electrical pulses in hexagonal patterns. Read More »

Synopsis: Bacteria Never Swim Alone
Biological Physics

Synopsis: Bacteria Never Swim Alone

Simulations and theory indicate that the “synchronized swimming” of bacteria occurs in much sparser suspensions of the microorganisms than expected. Read More »

Synopsis: Sensing Earthly Magnetic Fields

Synopsis: Sensing Earthly Magnetic Fields

An organic material’s resistance changes measurably in weak magnetic fields, with a sensitivity similar to that of migrating birds. Read More »

More Articles