2003/01/31 by Onofre Rojas, F. C. Alcaraz, F C Alcaraz · 3 citations
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.67.174401
published as Phys. Rev. B 67, 174401 (2003) · 23 pages, 15 figures
arxiv created 2003/03/02 · openalex publication_date 2003/05/05 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
The phase diagram of a coupled tetrahedral Heisenberg model is obtained. The quantum chain has a local gauge symmetry and its eigenspectrum is obtained by the composition of the eigenspectra of spin\ensuremath-(1)/(2) XXZ chains with arbitrary distribution of spin\ensuremath-(3)/(2) impurities. The phase diagram is quite rich with an infinite number of phases with ferromagnetic, antiferromagnetic, or ferrimagnetic order. In some cases the ground state and the low-lying eigenlevels of the model can be exactly calculated since they coincide with the eigenlevels of the exactly integrable XXZ chain. The thermodynamical properties of the model at low temperatures are also studied through finite-size analysis.