Ring-Exchange Interaction in Doubly Degenerate Orbital System

2010/02/01 by Joji Nasu, Sumio Ishihara · 2 citations
Materials Science · Physics and Astronomy · #Degenerate energy levels #Hamiltonian (control theory) #Interaction model #Magnetic and transport properties of perovskites and related materials #Mott insulator #Pairing #Physics of Superconductivity and Magnetism #Quadrupole #Rare-earth and actinide compounds #Strong interaction #Weak interaction #cond-mat.mtrl-sci #cond-mat.str-el

paper · pdf · doi:10.1143/jpsj.80.033704

published in Journal of the Physical Society of Japan 80(3), 033704 (Physical Society of Japan) · 5 pages, 5 figures

arxiv created 2010/02/01 · openalex publication_date 2011/02/25 · arxiv updated 2015/05/18 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

Ring-exchange (RE) interaction in Mott insulator with doubly degenerate e_g orbitals is studied. Hamiltonian for the RE interaction is derived by the perturbational calculation. A remarkably weak RE interaction destroys the orbital order caused by the order-by-fluctuation mechanism in the nearest-neighbor exchange-interaction model. A long range order of magnetic octupole moment, i.e. complex orbital wave functions, appears. Competition between octupole and quadrupole interactions strongly suppresses ordered moments.

Citations

• Effects of biquadratic exchange on the spectrum of elementary excitations in spin ladders
• Two Step Restoration of SU(2) Symmetry in a Frustrated Quantum Magnet
• Orbital Ordering and Frustration ofp-Band Mott Insulators
• Orbital ordering inLaMnO3:Electron-electron and electron-lattice interactions
• Quantum Behavior of Orbitals in Ferromagnetic Titanates: Novel Orderings and Excitations
• Deconfined Quantum Critical Points
• Fault-tolerant quantum computation by anyons
• Orbital order in classical models of transition-metal compounds
• SU(4) Theory for Spin Systems with Orbital Degeneracy