Covalency contributions to the electronic polarizability in dielectric compounds

S. Ishihara, M. Tachiki, T. Egami

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

The electron covalency contributions to the polarizability in oxide dielectric compounds are studied in the electron-lattice coupling model by means of the exact diagonalization technique. These contributions originate from the charge transfer between the anion and the cation sites which produces an electric dipole moment extended over the anion-cation bond distance. When a strong on-site Coulomb repulsion between electrons is included, the electronic system is found to undergo a transition between the ionic and Mott insulating phases, and the covalency contributions to the polarizability are largely enhanced near the phase boundary. It is suggested that the present results may explain the high indices of refraction observed in the titanium oxides and the birefringence in the ferroelectric compounds.

Original languageEnglish
Pages (from-to)16123-16128
Number of pages6
JournalPhysical Review B
Volume49
Issue number23
DOIs
Publication statusPublished - 1994 Jan 1

ASJC Scopus subject areas

  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Covalency contributions to the electronic polarizability in dielectric compounds'. Together they form a unique fingerprint.

  • Cite this