First-principles study of microscopic properties of the Nb antisite in LiNbO{sub 3}: Comparison to phenomenological polaron theory

Journal Article · Sat Nov 01 00:00:00 EDT 2008 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.78.184108· OSTI ID:21192481

Nahm, H H; Park, C H ^[1]

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1. Research Center for Dielectric and Advanced Matter Physics and Department of Physics, Pusan National University, Busan 609-735 (Korea, Republic of)

Through the first-principles local-density-approximation+Hubbard-U (LDA+U) electronic-structure calculation method, the microscopic properties of the Nb antisite (Nb{sub Li}) and the electron-lattice interaction are investigated. The atomic structure is found to depend on the capture of electrons at the defect level, and especially when the defect level is occupied by two electrons, the Nb{sub Li} undergoes a large-lattice-relaxation (LLR), accompanied with the formation of the deep level. The main driving force toward the LLR is suggested to be the orbital hybridization of the defect level state and the conduction-band state. As a result, the Nb{sub Li} defect exhibits a negative-U property. Based on the computational results, several well-known light-induced phenomena in LiNbO{sub 3} and the polaron model are discussed.

• OSTI ID: 21192481
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 78, Issue 18; Other Information: DOI: 10.1103/PhysRevB.78.184108; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
APPROXIMATIONS
CAPTURE
COMPARATIVE EVALUATIONS
CRYSTAL LATTICES
DEFECTS
DENSITY
DENSITY FUNCTIONAL METHOD
ELECTRONIC STRUCTURE
ELECTRONS
HUBBARD MODEL
INTERACTIONS
LITHIUM COMPOUNDS
NIOBATES
NIOBIUM
NIOBIUM COMPOUNDS
NIOBIUM OXIDES
OXYGEN COMPOUNDS
POLARONS
RELAXATION
SIMULATION