Entropy Driven Dimerization in a One-Dimensional Spin-Orbital Model

Abstract

We study a new version of the one-dimensional spin-orbital model with spins S=1 relevant to cubic vanadates. At small Hund's coupling J_H we discover dimerization in a pure electronic system solely due to a dynamical spin-orbital coupling. Above a critical value J_H, a uniform ferromagnetic state is stabilized at zero temperature. More surprisingly, we observe a temperature driven dimerization of the ferrochain, which occurs due to a large entropy released by dimer states. This dynamical dimerization seems to be the mechanism driving the peculiar intermediate phase of YVO_3.

5 pages, 4 figures

References in corpus (9)

• SU(4) Theory for Spin Systems with Orbital Degeneracy
• Orbital liquid in three dimensional Mott insulator: $LaTi{O}_3$
• Spin Dynamics and Orbital State in LaTiO_3
• Spin Order due to Orbital Fluctuations: Cubic Vanadates
• Transition between orbital orderings in YVO3
• Thermodynamics of the one-dimensional SU(4) symmetric spin-orbital model
• Orbitally Degenerate Spin-1 Model for Insulating V2O3
• Temperature driven crossover phenomena in the correlation lengths of the one-dimensional t-J model
• Theory for high spin systems with orbital degeneracy

Cited by in corpus (34)

• The density-matrix renormalization group
• Dynamical quantum phase transitions and the Loschmidt echo: A transfer matrix approach
• Fingerprints of spin-orbital physics in cubic Mott insulators: Magnetic exchange interactions and optical spectral weights
• Magnetic neutron scattering study of YVO3: Evidence for an orbital Peierls state
• Neutron diffraction study of YVO3, NdVO3, and TbVO3
• Fingerprints of spin-orbital entanglement in transition metal oxides
• Dimerization versus Orbital Moment Ordering in the Mott insulator YVO${}_3$
• Real-time dynamics at finite temperature by DMRG: A path-integral approach
• Optical study of orbital excitations in transition-metal oxides
• Thermally activated Peierls dimerization in ferromagnetic spin chains
• Spectral properties of orbital polarons in Mott insulators
• Application of the density matrix renormalization group method to finite temperatures and two-dimensional systems
• Orbital Wave and its Observation in Orbital Ordered Titanates and Vanadates
• Von Neumann Entropy Spectra and Entangled Excitations in Spin-Orbital Models
• One-dimensional orbital fluctuations and the exotic magnetic properties of YVO${}_3$
• Doping variation of anisotropic charge and orbital dynamics in Y1-xCaxVO3 : Comparison with La1-xSrxVO3
• Exotic spin orders driven by orbital fluctuations in the Kugel-Khomskii model
• Orbital superexchange and crystal field simultaneously at play in YVO3: resonant inelastic x-ray scattering at the V L edge and the O K edge
• Spin, orbital ordering and magnetic dynamics of LaVO3: magnetization, heat capacity and neutron scattering studies
• Defect states and excitations in a Mott insulator with orbital degrees of freedom: Mott-Hubbard gap versus optical and transport gaps in doped systems
• Defect states and spin-orbital physics in doped vanadates Y1-xCaxVO3
• Fingerprints of spin-orbital polarons and of their disorder in the photoemission spectra of doped Mott insulators with orbital degeneracy
• The dimerized ferromagnetic Heisenberg chain
• Orbital-Peierls State in NaTiSi2O6
• Magnetic excitations in one-dimensional spin-orbital models
• Charge and orbital order in transition metal oxides
• Jahn-Teller versus quantum effects in the spin-orbital material LuVO3
• Thermodynamics of a one-dimensional S=1/2 spin-orbital model
• Quantum Phase Transitions in the One-Dimensional S=1 Spin-Orbital Model: Implications for Cubic Vanadates
• Spin and orbital valence bond solids in a one-dimensional spin-orbital system: Schwinger boson mean field theory
• Orbital-controlled magnetic transition between gapful and gapless phases in the Haldane system with t2g-orbital degeneracy
• One-Dimensional S=1 Spin-Orbital Model with Uniaxial Single-Ion Anisotropy
• Spin-wave theory for dimerized ferromagnetic chains
• Doping a Mott insulator with orbital degrees of freedom