2016/09/01 by S. Ward, P. Bouillot, C. Kollath +10 · 1 citation
Physics and Astronomy · #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.118.177202
published as Phys. Rev. Lett. 118, 177202 (2017) · 6 pages, 3 figures plus supplementary material 7 pages 5 figures
arxiv created 2016/09/01 · arxiv updated 2017/05/03
The challenge of one-dimensional systems is to understand their physics beyond the level of known elementary excitations. By high-resolution neutron spectroscopy in a quantum spin ladder material, we probe the leading multiparticle excitation by characterizing the two-magnon bound state at zero field. By applying high magnetic fields, we create and select the singlet (longitudinal) and triplet (transverse) excitations of the fully spin-polarized ladder, which have not been observed previously and are close analogs of the modes anticipated in a polarized Haldane chain. Theoretical modelling of the dynamical response demonstrates our complete quantitative understanding of these states.