Magnetoelastic coupling across the field-induced transition of uranium mononitride
Abstract
Uranium mononitride (UN) displays a spin-flop-like transition for magnetic field applied along all principal crystallographic directions just below 60 T. Here, we report on ultrasound and magnetocaloric-effect results for UN in pulsed magnetic fields up to 65 T. The field-induced phase transition causes a discontinuous temperature decrease, indicating a larger magnetic entropy above the transition. Furthermore, we find pronounced anomalies in the acoustic properties, which signals strong spin-lattice interactions. A further anomaly observed at fields slightly above the transition is likely related to the formation of magnetic domains. A model based on the exchange-striction coupling mechanism well reproduces the strong renormalization of the acoustic properties.
- Publication:
-
Physical Review B
- Pub Date:
- July 2019
- DOI:
- 10.1103/PhysRevB.100.024417
- Bibcode:
- 2019PhRvB.100b4417G