2006/03/31 by R. G. Pereira, Rodrigo G. Pereira, J. Sirker +11 · 9 citations
Mathematics · Physics and Astronomy · #Algebraic structures and combinatorial models #Physics of Superconductivity and Magnetism #Quantum many-body systems #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.96.257202
published as Phys. Rev. Lett. 96, 257202 (2006) · 4 pages, 3 figures, published version
arxiv created 2006/06/28 · openalex publication_date 2006/06/28 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The longitudinal spin structure factor for the XXZ-chain at small wave vector q is obtained using Bethe ansatz, field theory methods, and the density matrix renormalization group. It consists of a peak with a peculiar, non-Lorentzian shape and a high-frequency tail. We show that the width of the peak is proportional to q2 for finite magnetic field compared to q3 for a zero field. For the tail we derive an analytic formula without any adjustable parameters and demonstrate that the integrability of the model directly affects the line shape.