Magnetostriction-driven muon localization in an antiferromagnetic oxide

Journal article

Magnetostriction results from the coupling between magnetic and elastic degrees of freedom. Though it is associated with a relatively small energy, we show that it plays an important role in determining the site of an implanted muon, so that the energetically favorable site can switch on crossing a magnetic phase transition. This surprising effect is demonstrated in the cubic rocksalt antiferromagnet MnO which undergoes a magnetostriction-driven rhombohedral distortion at the Néel temperature T_{N}=118  K. Above T_{N}, the muon becomes delocalized around a network of equivalent sites, but below T_{N} the distortion lifts the degeneracy between these equivalent sites. Our first-principles simulations based on Hubbard-corrected density-functional theory and molecular dynamics are consistent with the experimental data and help to resolve a long-standing puzzle regarding muon data on MnO, as well as having wider applicability to other magnetic oxides.

Authors: Bonfà, P; Onuorah, IJ; Lang, F; Timrov, I; Monacelli, L

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Physical Society
• Journal: Physical Review Letters
• Volume: 132
• Issue: 4
• Article number: 046701
• Place of publication: United States
• Publication date: 2024-01-24
• Acceptance date: 2023-11-20
• DOI: 10.1103/physrevlett.132.046701
• EISSN: 1079-7114
• ISSN: 0031-9007
• Pmid: 38335330
• Language: English