1998/11/07 by Chiranjeeb Buragohain, Subir Sachdev · 1 citation
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum many-body systems #Theoretical and Computational Physics #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.59.9285
published as Physical Review B 59, 9285 (1999). · 38 pages, including 12 figures
arxiv created 1998/11/07 · openalex publication_date 1999/04/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a general theory for the intermediate-temperature (T) properties of Heisenberg antiferromagnets of spin-S ions on p-leg ladders, valid for 2Sp even or odd. Following an earlier proposal for 2Sp even [Damle and Sachdev, Phys. Rev. B 57, 8307 (1998)], we argue that an integrable, classical, continuum model of a fixed-length, three-vector applies over an intermediate-temperature range; this range becomes very wide for moderate and large values of 2Sp. The coupling constants of the effective model are known exactly in terms of the energy gap above the ground state \ensuremathΔ (for 2Sp even), or a crossover scale T0 (for 2Sp odd). Analytic and numeric results for dynamic and transport properties are obtained, including some exact results for the spin-wave damping. Numerous quantitative predictions for neutron scattering and NMR experiments are made. A general discussion on the nature of T>0 transport in integrable systems is also presented: an exact solution of a toy model proves that diffusion can exist in integrable systems, provided proper care is taken in approaching the thermodynamic limit.