Molecular spin-orbit excitations in the J(eff)=1/2 frustrated spinel GeCo2O4

Article

关键词: MAGNETIC-PROPERTIES;    STATE;    ANTIFERROMAGNETISM;    TRANSITION;    CRYSTAL;    KCOF3;    ICE;   

DOI  :  10.1103/PhysRevB.84.054405

来源: SCIE

【 摘 要 】

We describe powder and single-crystal inelastic neutron scattering experiments on a spinel-type antiferromagnet GeCo2O4, represented by an effective total angular momentum J(eff) = 1/2. Several types of nondispersive short-range magnetic excitations were discovered. The scattering intensity maps in Q space are well reproduced by dynamical structure factor analyses using molecular model Hamiltonians. The results of analyses suggest that the molecular excitations below T-N arise from molecular ground states, one of which consists of antiferromagnetically coupled ferromagnetic subunits. The quasielastic excitations above T-N are interpreted as its precursor. A combination of frustration and J(eff) = 1/2 might induce these quantum phenomena.

【 授权许可】

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