2025/06/05 by Kumeda, Rio, Haraguchi, Yuya, Nishio-Hamane, Daisuke +3
#FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Strongly Correlated Electrons (cond-mat.str-el)
paper · doi:10.48550/arxiv.2506.05099
Metastable Co2Ti3O8 was synthesized through a topochemical reaction using Li2CoTi3O8 as the precursor, resulting in a vacancy-ordered spinel structure. Crystal structure analysis confirmed that Co ions selectively occupy the A-site, giving rise to a frustrated diamond lattice. Magnetic susceptibility and heat capacity measurements revealed antiferromagnetic order at 4.4 K, which is markedly suppressed compared to the negative Weiss temperature of ∼-27 K, indicating a high degree of frustration effects. Pulsed high-field magnetization measurements revealed a four-step successive magnetic phase transition, demonstrating that Co2Ti3O8 is a promising candidate for a frustrated J1-J2 diamond lattice. Additionally, the J2/J1 ration estimated from the molecular field approximation suggests the possibility of a spiral ordered ground state. These observations highlight the potential of frustrated magnetism in ordered spinel structures to expand the material search space for quantum magnetism, including magnetic skyrmions.