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Title: Single-ion anisotropy driven chiral magnetic order in a spin-1 antiferromagnetic chain
Chirality in magnetic systems gives rise to a wide range of exotic phenomena, yet its influence in S = 1 chains remains largely unexplored. Here, we present a comprehensive experimental study of a chiral antiferromagnetic (AFM) S = 1 chain, [Ni(pym)(H2O)4]SO4· H2O (pym = pyrimidine), where the Ni(II) octahedral orientation exhibits a four-fold chiral periodicity. Muon spin rotation measurements indicate the onset of long-range magnetic order below TN = 1.82(2) K. Neutron diffraction measurements reveal a chiral AFM order driven by a chiral modulation of the easy-axis anisotropy direction, rather than the typical scenario of Dzyaloshinskii-Moriya interactions, geometrical frustration or higher-order interactions. Inelastic neutron scattering (INS) measurements reveal dispersive spin-wave excitations well described by linear spin-wave theory, with Hamiltonian parameters J0 = 6.81(1)K (intrachain exchange), J′ 1a = −0.091(1)K (interchain exchange), and D = −3.02(1)K (easy-axis single-ion anisotropy). These parameters are further validated by Monte Carlo simulations of the magnetisation. Additionally, the INS data reveal multiple dispersionless bands, suggesting the presence of further excitations beyond the scope of linear spin-wave theory.  more » « less
Award ID(s):
2104167
PAR ID:
10704726
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Physical Society
Date Published:
Journal Name:
Physical Review B
ISSN:
2469-9950
Subject(s) / Keyword(s):
Chiral magnetism Antiferromagnetic spin chains S = 1 quantum magnets Nickel(II) compounds Magnetic anisotropy Long-range magnetic order
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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