Higgs mode and its decay in a two-dimensional antiferromagnet

Warning

This publication doesn't include Faculty of Arts. It includes Central European Institute of Technology. Official publication website can be found on muni.cz.
Authors

JAIN A. KRAUTLOHER M. PORRAS J. RYU G.H. CHEN D.P. ABERNATHY D.L. PARK J.T. IVANOV A. CHALOUPKA Jiří KHALIULLIN G. KEIMER B. KIM B.J.

Year of publication 2017
Type Article in Periodical
Magazine / Source Nature Physics
MU Faculty or unit

Central European Institute of Technology

Citation
Web http://www.nature.com/nphys/journal/v13/n7/full/nphys4077.html
Doi http://dx.doi.org/10.1038/NPHYS4077
Field Solid matter physics and magnetism
Keywords quantum magnetism; spin systems; spin-orbit coupling; condensate; spin excitations
Description Condensed-matter analogues of the Higgs boson in particle physics allow insights into its behaviour in different symmetries and dimensionalities(1). Evidence for the Higgs mode has been reported in a number of different settings, including ultracold atomic gases(2), disordered superconductors(3), and dimerized quantum magnets(4). However, decay processes of the Higgsmode(which are eminently important in particlephysics) have not yet been studied in condensed matter due to the lack of a suitable material system coupled to a direct experimental probe. A quantitative understanding of these processes is particularly important for low-dimensional systems, where the Higgs mode decays rapidly and has remained elusive to most experimental probes. Here, we discover and study the Higgs mode in a two-dimensional antiferromagnet using spin-polarized inelastic neutron scattering. Our spin-wave spectra of Ca2RuO4 directly reveal a well-defined, dispersive Higgs mode, which quickly decays into transverse Goldstone modes at the antiferromagnetic ordering wavevector. Through a complete mapping of the transverse modes in the reciprocal space, we uniquely specify the minimal model Hamiltonian and describe the decay process. We thus establish a novel condensed-matter platform for research on the dynamics of the Higgs mode.
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.