1997/05/26 by Ralph Werner, Claudius Gros · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #cond-mat
paper · pdf · doi:10.1103/physrevb.57.2897
published as Phys. Rev. B 57 (1998) 2897 · 7.1 pages, figures included
arxiv created 1997/05/26 · openalex publication_date 1998/02/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present a theory for the spin-Peierls transition in CuGeO3. We map the elementary excitations of the dimerized chain (solitons) on an effective Ising model. Inter-chain coupling (or phonons) then introduce a linear binding potential between a pair of soliton and anti-soliton, leading to a finite transition temperature. We evaluate, as a function of temperature, the order parameter, the singlet-triplet gap, the specific heat, and the susceptibility and compare with experimental data on CuGeO3. We find that CuGeO3 is close to a first-order phase transition. We point out, that the famous scaling law ∼δ2/3 of the triplet gap is a simple consequence of the linear binding potential between pairs of solitons and anti-solitons in dimerized spin chains.