Pseudo-easy-axis anisotropy in antiferromagnetic $S=1$ diamond-lattice systems Ni$X_{2}$(pym)$_{2}$
Abstract
We investigate the magnetic properties of antiferromagnetic diamond lattice, Ni(pyrimidine) ( = Cl, Br), hosting a single-ion anisotropy (SIA) orientation which alternates between neighbouring sites. Through neutron diffraction measurements of the = Cl compound, the ordered state spins are found to align collinearly along a pseudo-easy-axis, a unique direction created by the intersection of two easy planes. Similarities in the magnetization, exhibiting spin-flop transitions, and the magnetic susceptibility in the two compounds imply that the same magnetic structure and a pseudo-easy-axis is also present for = Br. We estimate the Hamiltonian parameters by combining analytical calculations and Monte-Carlo (MC) simulations of the spin-flop and saturation field. The MC simulations also reveal that the spin-flop transition occurs when the applied field is parallel to the pseudo-easy-axis. Contrary to conventional easy-axis systems, there exist field directions perpendicular to the pseudo-easy-axis for which the magnetic saturation is approached asymptotically and no symmetry-breaking phase transition is observed at finite fields.
Keywords
Cite
@article{arxiv.2405.15623,
title = {Pseudo-easy-axis anisotropy in antiferromagnetic $S=1$ diamond-lattice systems Ni$X_{2}$(pym)$_{2}$},
author = {S. Vaidya and A. Hernández-Melián and J. P. Tidey and S. P. M. Curley and S. Sharma and P. Manuel and C. Wang and G. L. Hannaford and S. J. Blundell and Z. E. Manson and J. L. Manson and J. Singleton and T. Lancaster and R. D. Johnson and P. A. Goddard},
journal= {arXiv preprint arXiv:2405.15623},
year = {2024}
}
Comments
9 pages, 8 figures