Abstract
We observe a wealth of multimagnon bound states in the strongly anisotropic spin-1 triangular antiferromagnet FeI2 using time-domain terahertz spectroscopy. These unconventional excitations can arise in ordered magnets due to attractive magnon-magnon interactions and alter their properties. We analyze the energy-magnetic field spectrum via an exact diagonalization method for a dilute gas of interacting magnons and detect up to 4- and 6-magnon bound states, hybridized with single magnons. This zoo of tunable interacting quasiparticles provides a unique platform to study decay and renormalization, reminiscent of the few-body problems found in cold-atom, nuclear, and particle physics.
| Original language | English |
|---|---|
| Article number | 267201 |
| Journal | Physical Review Letters |
| Volume | 127 |
| Issue number | 26 |
| DOIs | |
| State | Published - Dec 24 2021 |
Funding
Work at JHU (A. L, N. P. A.) was supported as part of the Institute for Quantum Matter, an EFRC funded by the DOE BES under DE-SC0019331. A. L. and N. P. A thank Howard Katz and Jinfeng Han from the Department of Materials Science and Engineering at JHU for providing the necessary equipment to prepare the sample for measurements. The work at GT (X. B., Z. L. D., M. M.) and the University of Tennessee (S.-S. Z., H. Z., C. D. B.) was supported by the DOE BES under Award No. DE-SC-0018660. The work by H. Z. was supported by the Graduate Advancement, Training and Education (GATE) program of UTK and ORNL. Growth of crystals is based upon work supported by the National Science Foundation [Platform for the Accelerated Realization, Analysis, and Discovery of Interface Materials (PARADIM)] under Cooperative Agreement No. DMR-1539918.
| Funders | Funder number |
|---|---|
| EFRC | |
| National Science Foundation | DMR-1539918 |
| Basic Energy Sciences | DE-SC0019331, DE-SC-0018660 |
| Oak Ridge National Laboratory | |
| Johns Hopkins University | |
| University of Tennessee, Knoxville |