Abstract
We have made the first observation of the nuclear Barnett effect. In the electronic Barnett effect, which was first observed in 1915 by Samuel Barnett, a ferromagnetic rod was spun about its long axis and a magnetization developed in the rod along the axis of rotation. This effect is caused by the coupling between the angular momentum of the electronic spins in the sample and the rotational motion of the rod. In our experiment, we measured the nuclear Barnett effect by rotating a sample of water at rotational speeds up to 13.5 kHz in a weak magnetic field and observed a change in the polarization of the protons in the sample that is proportional to the frequency of rotation. We measured this polarization by observing the change in the size of a nuclear magnetic resonance (NMR) signal. No NMR frequency shift was observed due to rotation, meaning that this magnetization was not produced by a real magnetic field.
- Received 16 July 2018
- Revised 21 December 2018
DOI:https://doi.org/10.1103/PhysRevLett.122.177202
© 2019 American Physical Society
Physics Subject Headings (PhySH)
Synopsis
Fast Rotation Polarizes Water
Published 2 May 2019
Researchers demonstrate that they can magnetize hydrogen nuclei in water by rotating the liquid at high speeds.
See more in Physics