Low-temperature time-resolved vacuum UV spectroscopy of potassium pentaborate crystals / Ogorodnikov IN,Pustovarov VA,Kirm M,Kruzhalov AV,Isaenko LI // OPTICS AND SPECTROSCOPY. - 2002. - V. 92, l. 5. - P. 702-709.

ISSN/EISSN:

0030-400X / нет данных

Type:

Article

Abstract:

For the first time, subnanosecond time resolution is attained in the low-temperature (at 7 K) measurements of the photoluminescence (PL) spectra (2-6 eV), the PL excitation spectra (4-32 eV), the PL kinetics, and the reflection spectra (4-21 eV) of undoped potassium pentaborate KB5O8..4H(2)O (KB5) crystals under selective photoexcitation by synchrotron radiation. The PL peaks associated with the intrinsic defects of the KB5 lattice are detected. The PL bands resulting from radiative annihilation of the localized and self-localized electron excitations are singled out; these excitations are most efficiently photogenerated at the fundamental absorption edge in the region where the free exciton formation is expected. The difference between the PL spectra of the fast and slow components is revealed. An effective low-temperature energy transport over the KB5 hydrogen sublattice is deduced from a drop in efficiency of PL excitation in the interband-transition region as a result of nonradiative energy loss. Long-term vacuum UV irradiation of a KB5 crystal at 7 K gives rise to defects in the hydrogen sublattice, which facilitate localization of the electron excitations and reduce the effective length of their diffusion. This leads to a decrease in the nonradiative energy loss, thus enhancing the efficiency of the PL photoexcitation in the band-to-band transition region (C) 2002 MAIK ``Nauka/Interperiodica{''}.

Author keywords:

H2O ICE; LUMINESCENCE; ULTRAVIOLET; GENERATION; RADIATION

DOI:

10.1134/1.1481135

Web of Science ID:

ISI:000176523100010

Соавторы в МНС:

Другие поля

Поле	Значение
Month	MAY
Publisher	OPTICAL SOC AMER
Address	2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA
Language	English
Keywords-Plus	H2O ICE; LUMINESCENCE; ULTRAVIOLET; GENERATION; RADIATION
Research-Areas	Optics; Spectroscopy
Web-of-Science-Categories	Optics; Spectroscopy
ResearcherID-Numbers	Isaenko, Ludmila/H-7620-2013 Isaenko, Ludmila/A-5272-2014 Ogorodnikov, Igor/B-4162-2011 Kirm, Marco/M-1533-2016
ORCID-Numbers	Ogorodnikov, Igor/0000-0002-4700-2340 Kirm, Marco/0000-0002-1833-6894
Number-of-Cited-References	46
Journal-ISO	Opt. Spectrosc.
Doc-Delivery-Number	568BT