Title :
Study epitaxially strained KNbO3/NaNbO3 superlattice using first-principle´s calculations
Author :
Li, Zhanfang ; Lü, Tianquan ; Cao, Wenwu
Abstract :
The changes of crystal structure, zone-center phonon, polarization and dielectric constant with epitaxial strain in KNbO3/NaNbO3 (KNO/NNO) superlattice have been studied using density functional theory (DFT) within the local-density approximation (LDA). Strain induced structural phase transitions have been identified from tetragonal to monoclinic then to orthorhombic when the in plane misfit strain changes from -1.25% to -0.1%. The polarization amplitude is the highest in the orthorhombic phase, reaching more than 70 muC/cm2, and the dielectric constant peaks at the phase boundaries.
Keywords :
ab initio calculations; crystal structure; density functional theory; dielectric materials; dielectric polarisation; ferroelectric transitions; permittivity; phonons; potassium compounds; sodium compounds; superlattices; DFT; KNbO3-NaNbO3; LDA; crystal structure; density functional theory; dielectric constant; epitaxially strained superlattice; first-principles calculations; local-density approximation; phase boundaries; plane misfit strain; polarization; strain induced structural phase transitions; tetragonal-monoclinic-orthorhombic transitions; zone-center phonon; Capacitive sensors; Dielectric constant; Electrons; Environmentally friendly manufacturing techniques; Ferroelectric materials; Lattices; Lead compounds; Polarization; Solids; Superlattices;
Conference_Titel :
Applications of Ferroelectrics, 2009. ISAF 2009. 18th IEEE International Symposium on the
Conference_Location :
Xian
Print_ISBN :
978-1-4244-4970-5
Electronic_ISBN :
1099-4734
DOI :
10.1109/ISAF.2009.5307525
