The gap vs critical temperature ratio in Peierls-type phase transitions

2011/11/04 by Gennady Y. Chitov, Chitov, Gennady Y.
Materials Science · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #Force Microscopy Techniques and Applications #Material Dynamics and Properties #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el

paper · pdf · doi:10.48550/arxiv.1111.1201

4 pages, 2 figures; Published in Proceedings of the International Symposium "Multiferroics-3", Sochi, Russia, 4-8 September, 2011, pp. 163-167

arxiv created 2011/11/04 · openalex publication_date 2011/11/04 · arxiv updated 2011/11/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

We analyze a 2D spin-pseudospin model, where the pseudospins represents the charge degrees of freedom. The model is known to undergo a phase transition with the simultaneous appearance of the long-range charge order and the spin gap. We show how the gap vs critical temperature ratio (also called the BCS ratio) gets renormalized from the classical non-interacting value. This value is also universal in the sense that is does not depend on the microscopic parameters of the model, and must be the same for various types of the Peierls-like transitions where the spin gap is accompanied by the structural, orbital or charge order.

Related

• Pseudospin Symmetry, Peierls Instability, and Charge Density Wave in a One-Dimensional Tight-Binding Model
• The Universal Gap-to-Critical Temperature Ratio in Superconductors: a Statistical Mechanical Perspective
• Universal behavior of the BCS energy gap
• Spin-Peierls transition of the dimer phase of the J₁-J₂ model:\n Energy cusp and CuGeO₃ thermodynamics
• Quantum spin chains with bond dissipation