Spin and Hole Dynamics in Carrier-Doped Quantum Haldane Chain

27th International Conference on Low Temperature Physics

Yokoo, T.^1,2 ; Itoh, S.^1,2 ; Ibuka, S.^1 ; Yoshizawa, H.^3 ; Akimitsu, J.^4

Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Ibaraki, Tsukuba

305-0801, Japan^1

Materials and Life Science Experimental Facility, J-PARC Center, Ibaraki, Tokai, 319-1106, Japan^2

Institute for Solid State Physics, University of Tokyo, Ibaraki, Tokai, 319-1106, Japan^3

Department of Physics and Mathematics, Aoyama-Gakuin University, Kanagawa, Sagamihara, 229-8558, Japan^4

关键词: Focus of Attention;    Haldane chains;    Hole dynamics;    Multiple degrees of freedom;    Pulsed neutron;    Quantum spin;    Spectral weight;    Spin-Peierls state;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/568/4/042035/pdf
DOI  :  10.1088/1742-6596/568/4/042035

来源: IOP

【 摘 要 】

Quantum spins in one-dimensional (1D) chains exhibit characteristic features such as the Haldane gap (S 1) and the spin-Peierls state (S 1/2). Multiple degrees of freedom associated with quantum spins have recently become a focus of attention. We present here the spin dynamics in lightly hole-doped Nd2-xCaxBaNiO5(x 0.1), a 1D Haldane system, using pulsed neutron inelastic scattering. The entire dispersion of the 1D Haldane chain was clearly observed with a ∼14 meV spin gap (Haldane gap) at the magnetic zone center. Below the gap, much spectral weight was observed, indicating an in-gap state possibly originating from the doped holes in Haldane chains.