Crystal growth, Nd distribution and luminescence properties of (Na0.425+xLu0.575−x−yNdy)F2.15−2x single crystals

✍ Scribed by Yuki Furuya; Hidehiko Tanaka; Kentaro Fukuda; Noriaki Kawaguchi; Yuui Yokota; Takayuki Yanagida; Valery Chani; Martin Nikl; Akira Yoshikawa

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 945 KB
• Volume: 318
• Category: Article
• ISSN: 0022-0248
• DOI: 10.1016/j.jcrysgro.2010.11.048

✦ Synopsis

a b s t r a c t (Na 0.425 + x Lu 0.575 À x À y Nd y )F 2.15 À 2x (x ¼ 0, y ¼0, 0.001, 0.01, 0.05, 0.1, 0.2; x ¼ 7 0.01, 0.02, 0.05, y ¼0.05) single crystals were grown from the melt using the precise atmosphere control type Micro-Pulling-Down (m-PD) method to examine their potential as a new VUV scintillators. The grown crystals were singlephase materials with fluorite type structure (Fm À 3m, Z¼ 4) as confirmed by XRD and had good crystallinity. The distribution of the crystal constituents in axial and radial directions was evaluated, and only negligible non-uniformity along growth axis was detected. The crystals demonstrated 70-90% transmittance above 176-188 nm wavelength and Nd 3 + 5d-4f luminescence (when exited by X-ray) observed around 185 nm. Both 5d-4f absorption and emission peaks shifted to longer wavelength region.

The radioluminiscence measurements under 5.5 MeV a-ray excitation ( 241 Am) demonstrated the light yield of 35-90 [Ph/5.5 MeV-a] and the decay time of 5.5-7.5 ns.