Физика Низких Температур: Том 46, Выпуск 12 (Декабрь 2020), c. 1386-1393 ( к оглавлению , назад )
Low-temperature luminescence of catangasite single crystals under excitation by vacuum ultraviolet synchrotron radiation
A. P. Kozlova1, O. A. Buzanov2, V. Pankratova3, and V. Pankratov3
1National University of Science and Technology «MISiS», Moscow 119049, Russia
2JSC Fomos-Materials, Moscow 107023, Russia
3Institute of Solid State Physics, University of Latvia, Riga LV-1063, Latvia
Received July 24, 2020, published online October 21, 2020
The luminescent properties of Ca3TaGa3Si2O14 (CTGS, catangasite) single crystals have been studied by means of the vacuum ultraviolet excitation spectroscopy utilizing synchrotron radiation from 1.5 GeV storage ring of MAX IV synchrotron facility. Two emission bands at 320 nm (3.87 eV) and 445 nm (2.78 eV) have been detected. Examining excitation spectra in vacuum ultraviolet spectral range, the 320 nm emission band was explained as the emission band of self-trapped exciton in CTGS single crystal. Its atomic struc-ture is discussed. It is also proposed that the 445 nm (2.78 eV) emission in the CTGS is due to the F centers, which have shown a well-resolved excitation (absorption) band at 5.1 eV (243 nm).
Key words: catangasite, langasite, langatate, VUV luminescence spectroscopy, synchrotron radiation.