2008/03/04 by M. Naka, Makoto Naka, Aya Nagano +1 · 2 citations
Engineering · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Magneto-Optical Properties and Applications #Multiferroics and related materials #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.77.224441
15 pages, 23 figures
arxiv created 2008/03/04 · openalex publication_date 2008/06/27 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Dielectric and magnetic phenomena in spin- and charge-frustrated system RFe2O4 (R is a rare-earth metal ion) are studied. An electronic model for charge, spin, and orbital degrees in a pair of triangular-lattice planes is derived. We analyze this model by utilizing the mean-field approximation and the Monte Carlo simulation in a finite size cluster. A threefold-type charge-ordered structure with charge imbalance between the planes is stabilized in finite temperatures. This polar charge order is reinforced by spin ordering of Fe ions. This magnetodielectric phenomenon is caused by spin frustration and charge-spin coupling in the exchange interaction. We show cross-correlation effect in magnetic- and electric-field responses. Oxygen-deficiency effect as an impurity effect in a frustrated charge-spin coupled system is also examined.