Spin excitations in an anisotropic bond-alternating quantum S=1 chain in a magnetic field: Contrast to Haldane spin chains

M. Hagiwara, L. P. Regnault, A. Zheludev, A. Stunault, N. Metoki, T. Suzuki, S. Suga, K. Kakurai, Y. Koike, P. Vorderwisch, Jaiho Chung

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

Inelastic neutron scattering experiments on the S=1 quasi-one-dimensional bond-alternating antiferromagnet Ni(C9D24N4)(NO2)ClO4 have been performed under magnetic fields below and above a critical field Hc at which the energy gap closes. Normal field dependence of Zeeman splitting of the excited triplet modes below Hc has been observed, but the highest mode is unusually small and smears out with increasing field. This can be explained by an interaction with a low-lying two magnon continuum at q=π that is present in dimerized chains but absent in uniform ones. Above Hc, we find only one excited mode, in stark contrast with three massive excitations previously observed in the structurally similar Haldane-gap material NDMAP [A. Zheludev, Phys. Rev. BPRBMDO0163-1829 68, 134438 (2003)10.1103/PhysRevB.68.134438].

Original languageEnglish
Article number177202
JournalPhysical Review Letters
Volume94
Issue number17
DOIs
Publication statusPublished - 2005 May 6
Externally publishedYes

    Fingerprint

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Hagiwara, M., Regnault, L. P., Zheludev, A., Stunault, A., Metoki, N., Suzuki, T., Suga, S., Kakurai, K., Koike, Y., Vorderwisch, P., & Chung, J. (2005). Spin excitations in an anisotropic bond-alternating quantum S=1 chain in a magnetic field: Contrast to Haldane spin chains. Physical Review Letters, 94(17), [177202]. https://doi.org/10.1103/PhysRevLett.94.177202