Abstract
The search for new elementary particles is one of the most basic pursuits in physics, spanning from subatomic physics to quantum materials. Magnons are the ubiquitous elementary quasiparticle to describe the excitations of fully-ordered magnetic systems. But other possibilities exist, including fractional and multipolar excitations. Here, we demonstrate that strong quantum interactions exist between three flavors of elementary quasiparticles in the uniaxial spin-one magnet FeI2. Using neutron scattering in an applied magnetic field, we observe spontaneous decay between conventional and heavy magnons and the recombination of these quasiparticles into a super-heavy bound-state. Akin to other contemporary problems in quantum materials, the microscopic origin for unusual physics in FeI2 is the quasi-flat nature of excitation bands and the presence of Kitaev anisotropic magnetic exchange interactions.
| Original language | English |
|---|---|
| Article number | 4199 |
| Journal | Nature Communications |
| Volume | 14 |
| Issue number | 1 |
| DOIs | |
| State | Published - Dec 2023 |
Funding
We thank Tyrel McQueen for his help with crystal growth at PARADIM. The work of X.B., Z.L.D., and M.M. at Georgia Tech was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under award DE-SC-0018660. The work of H.Z. at the Oak Ridge National Laboratory was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. The work of S.-S.Z. and C.D.B. at the University of Tennessee was supported by the Lincoln Chair of Excellence in Physics. Growth of FeI2 crystals was supported by the National Science Foundation’s PARADIM (Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials) under Cooperative Agreement No. DMR-1539918. Some of this work were performed in part at the Materials Characterization Facility at Georgia Tech that is jointly supported by the GT Institute for Materials and the Institute for Electronics and Nanotechnology, which is a member of the National Nanotechnology Coordinated Infrastructure supported by the National Science Foundation under Grant No. ECCS-2025462. This research used resources at the High Flux Isotope Reactor and Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. We thank Tyrel McQueen for his help with crystal growth at PARADIM. The work of X.B., Z.L.D., and M.M. at Georgia Tech was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division under award DE-SC-0018660. The work of H.Z. at the Oak Ridge National Laboratory was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division. The work of S.-S.Z. and C.D.B. at the University of Tennessee was supported by the Lincoln Chair of Excellence in Physics. Growth of FeI crystals was supported by the National Science Foundation’s PARADIM (Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials) under Cooperative Agreement No. DMR-1539918. Some of this work were performed in part at the Materials Characterization Facility at Georgia Tech that is jointly supported by the GT Institute for Materials and the Institute for Electronics and Nanotechnology, which is a member of the National Nanotechnology Coordinated Infrastructure supported by the National Science Foundation under Grant No. ECCS-2025462. This research used resources at the High Flux Isotope Reactor and Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. 2
| Funders | Funder number |
|---|---|
| GT Institute for Materials | ECCS-2025462 |
| National Science Foundation | DMR-1539918 |
| U.S. Department of Energy | |
| Office of Science | |
| Basic Energy Sciences | |
| Oak Ridge National Laboratory | |
| Division of Materials Sciences and Engineering | DE-SC-0018660 |