Field-induced multi- Q states in a pyrochlore Heisenberg magnet
Year: 2025
Type: article
Abstract: We construct exact ground states of the J 1 − J 3 b classical Heisenberg model on the pyrochlore lattice in the presence of a magnetic field. They are noncoplanar multi- Q ⃗ spin configurations with a large magnetic unit cell that generalize the previously found coplanar sublattice pairing states. Using linear spin-wave theory, we show that entropy favors these multi- Q ⃗ states at low temperatures in high magnetic fields. This is confirmed by Monte Carlo simulations, and a phase diagram is constructed. We also calculate the zero-temperature dynamical structure factor. Besides the usual Goldstone modes associated with the ordering Q ⃗ s , we find high intensity gapless modes at momenta where there are no Bragg peaks.
DOI: 10.1103/5rsg-2klm
Authors: Cecilie Glittum, Olav F. Syljuåsen
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Funder: Universitetet i Oslo
OpenAlex ID: W4411205359