Crystal growth and ferroelectric property of Na(0.5)K(0.5)NbO(3) and Mn-doped Na(0.5)K(0.5)NbO(3) crystals grown by floating zone method

• Published in: Journal of the European Ceramic Society Vol. 30; no. 2; pp. 301 - 306
• Main Authors: Inagaki, Yumi, Kakimoto, Ken-Ichi, Kagomiya, Isao
• Format: Journal Article
• Language: English
• Published: 01.01.2010
• ISSN: 0955-2219
• DOI: 10.1016/j.jeurceramsoc.2009.05.050

Na(0.5)K(0.5)NbO(3) (NKN) and Mn-doped NKN crystals, which are one of the promising candidates of lead-free piezoelectric materials, were grown by using a floating zone (FZ) method. The resulting crystal growth was compared with crystal growth that resulted from using a flux method in a previous study. In the crystal grown by FZ method under where the growth rate was controlled to 3 mm/h, thin layers formed parallel and perpendicular directions to the growth direction. In the crystal grown by FZ method, the crystal structure could not be classified as having the orthorhombic lattice of Amm2, which was observed in the crystal grown using a flux method. It was found that doped Mn was substituted in the perovskite-type lattice of NKN. Pure NKN crystals showed 90' domains that had a zig-zag shape, whereas Mn-doped NKN crystals were aligned to the domain layers in straight lines. It was confirmed that Mn-doped NKN crystal showed a square P-E hysteresis loop.