Emergent many-body composite excitations of interacting spin-1/2 trimers.

Understanding exotic forms of magnetism in quantum spin systems is an emergent topic of modern condensed matter physics. Quantum dynamics can be described by particle-like carriers of information, known-as quasiparticles that appear from the collective behaviour of the underlying system. Spinon excitations, governing the excitations of quantum spin-systems, have been accurately calculated and precisely verified experimentally for the antiferromagnetic chain model.

Cluster spin-glass-like dynamics in Mn-rich LaNiMnOferromagnetic insulator.

We report on the physical properties of Mn-rich, nonstoichiometric LaNiMnOferromagnetic insulator, prepared by sol-gel method. The single-phase orthorhombicstructure for the compound was confirmed by x-ray diffraction measurements. Dc magnetization measurements revealed a high saturation magnetization of ∼5.

Experimental observation of Bethe strings.

Almost a century ago, string states-complex bound states of magnetic excitations-were predicted to exist in one-dimensional quantum magnets. However, despite many theoretical studies, the experimental realization and identification of string states in a condensed-matter system have yet to be achieved. Here we use high-resolution terahertz spectroscopy to resolve string states in the antiferromagnetic Heisenberg-Ising chain SrCoVO in strong longitudinal magnetic fields.