2025/08/16 by Tomer Dollberg, Dollberg, Tomer, Moshe Schechter +1
Materials Science · Physics and Astronomy · Chemistry · #Magnetism in coordination complexes #Advanced Condensed Matter Physics #Advanced NMR Techniques and Applications
paper · pdf · doi:10.48550/arxiv.2508.11994
We theoretically investigate the influence of off-diagonal dipolar interactions in the mixed-anisotropy magnet LiHoxEr1-xF4. Motivated by experimental observations showing an unexpectedly rapid suppression of the ferromagnetic transition temperature Tc upon substitution of Ho by Er ions, we use Monte Carlo simulations incorporating off-diagonal dipolar terms to elucidate the underlying physical mechanism. Our results reveal that, unlike in the diluted magnet LiHoxY1-xF4, where dilution weakens the effect of these interactions, substitution by planar Er ions amplifies it. This leads to a pronounced reduction of Tc, closely matching experimental data, thereby resolving discrepancies with mean-field predictions. The findings underscore the essential role of off-diagonal dipolar interactions in determining the magnetic properties of mixed-anisotropy dipolar systems.