2005/12/31 by Ikumi Honda, Kiyosi Terao
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.mtrl-sci #cond-mat.other
paper · pdf · doi:10.1143/jpsj.75.044704
published as J. Phys. Soc. Jpn 75 (2006) 044704 · 4 pages, 1 figure. Accepted by JPSJ. Clarified some setences. Corrected typos
arxiv created 2006/02/14 · openalex publication_date 2006/04/13 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We study the effects of magnetoelastic coupling on the degenerate ground state of the spin-1/2 antiferromagnetic Heisenberg model for the regular triangular spin cluster. Static displacement of spins spontaneously lifts the degeneracy of the ground state through the distance dependence of exchange coupling, i.e., a spin Jahn-Teller mechanism takes place. On the other hand, dynamical displacement does not lift the degeneracy, though the cluster distorts spontaneously. The energy decrease obtained by dynamical theory is twice as large as that obtained by static theory because of quantum fluctuation.