Haldane energy gap of a doped linear-chain Heisenberg antiferromagnet

1993/01/28 by Zhong‐Yi Lu, Zhong-Yi LU, Zhao-Bin +4
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Boson #Condensed matter physics #Heisenberg model #Impurity #Lambda #Magnetic and transport properties of perovskites and related materials #Pairing #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Spin (aerodynamics) #Spins #Superconductivity #cond-mat

paper · pdf · doi:10.1103/physrevb.47.12276

REVTEX, 12 pages, no figures

arxiv created 1993/01/28 · openalex publication_date 1993/05/01 · arxiv updated 2016/08/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05

Abstract

Using the valence-bond-solid (VBS) approach and the Schwinger-boson mean-field approximation, we study the dependence of the Haldane gap of a spin-1 linear-chain Heisenberg antiferromagnet on impurity doping with different spins. The impurity spins affect the singlet pairing order parameter \ensuremathΔ and the constraint factor \ensuremathλ. As a result, the Haldane gap is reduced by a factor \ensuremath∼n_i^2/3, with n_i as the impurity concentration, and eventually collapses at n_i\ensuremath∼1/\ensuremathξ with \ensuremathξ as the VBS correlation length. This theoretical prediction can be verified by neutron-scattering experiments.

Citations

• Critical theory of quantum spin chains
• Classical Spins in Superconductors
• Quantum spin chains and the Haldane gap
• Nonlinear Field Theory of Large-Spin Heisenberg Antiferromagnets: Semiclassically Quantized Solitons of the One-Dimensional Easy-Axis Néel State
• Continuum dynamics of the 1-D Heisenberg antiferromagnet: Identification with the O(3) nonlinear sigma model
• BOUND STATE IN SUPERCONDUCTORS WITH PARAMAGNETIC IMPURITIES