1999/08/03 by L. Campos Venuti, Lorenzo Campos Venuti, Elisa Ercolessi +4 · 2 citations
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Theoretical and Computational Physics #cond-mat.str-el
paper · pdf · doi:10.1142/s0217979202010099
published as Int. Jou. Mod. Phys. B Vol. 16 No.9, 1363 (2002) · 11 pages, 4 eps figures
arxiv created 1999/08/03 · openalex publication_date 2002/04/10 · arxiv updated 2009/11/30 · openalex created_date 2020/11/23 · openalex updated_date 2026/07/28
We investigate both numerically and analytically the behavior of a spin-1 antiferromagnetic isotropic Heisenberg chain in an external uniform magnetic field. Extensive DMRG studies of chains up to N = 80 sites extend previous analyses and obtain the zero-temperature correlation functions. We argue that, despite the presence of a magnetic field, the model is still well described by an O(3) nonlinear σ-model. A saddle-point analysis, that also includes Gaussian fluctuations, is developed for the latter both at zero and finite temperatures. Its predictions are compared with those of the numerical analysis and with the existing experimental literature.