2008/02/29 by George Jackeli, G. Jackeli, D. I. Khomskii +1 · 3 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magnetic and transport properties of perovskites and related materials #Physics of Superconductivity and Magnetism #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.100.147203
published as Phys. Rev. Lett. 100, 147203 (2008) · to appear in Phys. Rev. Lett
arxiv created 2008/03/18 · openalex publication_date 2008/04/09 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We discuss the ground state of the spin-orbital model for spin-one ions with partially filled t2g levels on a honeycomb lattice. We find that the orbital degrees of freedom induce a spontaneous dimerization of spins and drive them into nonmagnetic manifold spanned by hard-core dimer (spin-singlet) coverings of the lattice. The cooperative "dimer Jahn-Teller" effect is introduced through a magnetoelastic coupling and is shown to lift the orientational degeneracy of dimers leading to a peculiar valence bond crystal pattern. The present theory provides a theoretical explanation of nonmagnetic dimerized superstructure experimentally seen in Li2RuO3 compound at low temperatures.