2003/09/11 by M. T. Batchelor, X. -W. Guan, X.-W. Guan +3 · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Antiferromagnetism #Bethe ansatz #Ferromagnetism #Heisenberg model #Magnetization #Phase diagram #Physics of Superconductivity and Magnetism #Quantum #Quantum many-body systems #Quantum phase transition #Saturation (graph theory) #cond-mat.stat-mech
paper · pdf · doi:10.1023/b:joss.0000037225.79748.98
published as J. Stat. Phys. 116 (2004) 571-589 · 20 pages, 2 figures
arxiv created 2003/09/11 · openalex publication_date 2004/08/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We investigate the quantum phase diagram of the exactly solved mixed spin-(1/2,1) ladder via the thermodynamic Bethe ansatz (TBA). In the absence of a magnetic field the model exhibits three quantum phases associated with su(2), su(4) and su(6) symmetries. In the presence of a strong magnetic field, there is a third and full saturation magnetization plateaux within the strong antiferromagnetic rung coupling regime. Gapless and gapped phases appear in turn as the magnetic field increases. For weak rung coupling, the fractional magnetization plateau vanishs and exhibits new quantum phase transitions. However, in the ferromagnetic coupling regime, the system does not have a third saturation magnetization plat eau. The critical behaviour in the vicinity of the critical points is also derived systematically using the TBA.