Thermal spin dynamics of Kitaev magnets: Scattering continua and magnetic field induced phases within a stochastic semiclassical approach

Autor(en)

Oliver Franke, Dumitru Cǎlugǎru, Andreas Nunnenkamp, Johannes Knolle

Abstrakt

The honeycomb magnet RuCl3 is a prime candidate material for realizing the Kitaev quantum spin liquid (QSL), but it shows long-range magnetic order at low temperature. Nevertheless, its broad inelastic neutron scattering (INS) response at finite frequency has been interpreted as that of a "proximate QSL."A moderate in-plane magnetic field indeed melts the residual zigzag order, giving rise to peculiar intermediate-field phases before the high-field polarized state. In INS measurements the low-frequency spin waves disappear, leading to a broad scattering continuum in the field-induced intermediate regime, whose nature is currently under debate. Here, we study the magnetic-field-dependent spin dynamics of the K model within a stochastic semiclassical treatment, which incorporates the effect of finite-temperature fluctuations. At temperatures relevant for INS experiments, we show how the excitations of the zigzag phase broaden and that the different intermediate phases all show a similar continuum response. We discuss the implications of our results for experiments and highlight the importance of distinguishing finite-temperature fluctuations from genuine quantum fractionalization signatures in frustrated magnets.

Organisation(en)

Quantenoptik, Quantennanophysik und Quanteninformation

Externe Organisation(en)

Technische Universität München, Freie Universität Berlin (FU), Princeton University, University of Cambridge, Munich Center for Quantum Science and Technology (MCQST), Imperial College London

Journal

Physical Review B

Band

106

ISSN

2469-9950

DOI

https://doi.org/10.1103/PhysRevB.106.174428

Publikationsdatum

11-2022

Peer-reviewed

Ja

ÖFOS 2012

103017 Magnetismus

ASJC Scopus Sachgebiete

Electronic, Optical and Magnetic Materials, Condensed Matter Physics

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/fe41a66c-67ea-4cd0-b12b-a658ffe152c0