Level repulsion in quantum magnets

Neutron measurements at Oak Ridge National Laboratory's Spallation Neutron Source are giving physicists new insight into the behavior of quantum magnets. A research team led by Young-June Kim from the University of Toronto used neutron spectroscopy to observe a novel type of energy band repulsion in a magnetic insulator.

The study adds to scientists' understanding of quasiparticles, a theoretical concept that describes many inside a material. "One general rule for quasiparticles is that energy levels or bands don't like to intersect – what's known as level repulsion," said ORNL coauthor Garrett Granroth. "In this paper, we show a specific example of a level repulsed by a continuum of states in a quantum magnet, which hasn't been seen before."

Understanding the intricate magnetism of this material may help researchers predict analogous behavior in other complex systems such as superconductors. The team's results are published in Nature Physics.


Explore further

Calcium-48's 'neutron skin' thinner than previously thought

More information: K. W. Plumb et al. Quasiparticle-continuum level repulsion in a quantum magnet, Nature Physics (2015). DOI: 10.1038/nphys3566
Journal information: Nature Physics

Citation: Level repulsion in quantum magnets (2015, December 2) retrieved 21 August 2019 from https://phys.org/news/2015-12-repulsion-quantum-magnets.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
9 shares

Feedback to editors

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more