Effect of Uniaxial Stress on Exciton Luminescence in CsI Crystals

Defect Creation under UV Irradiation of CsI:Pb Crystals in Pb2+-Induced Absorption Bands Investigated by Luminescence Methods

“…Unlike [6,11], in the present paper the photostimulated recombination {e --+ V K } STE luminescence is considered. Under the uniaxial stress, which leads to the lowering of the crystal lattice symmetry, hole self-trapping processes should have some peculiarities.…”

“…However, our experiments have shown that the temperature dependences of the intensities of both the 4.29 eV and 3.65 eV emissions do not change under the stress. No stress-induced changes in the 3.65 eV/4.29 eV emission intensity ratio have been detected in [6] under excitation in the exciton absorption region of CsI. Therefore one may conclude that in CsI, due to a high potential barrier between the on-centre and off-centre STE configurations, the relative change of this barrier under the stress is so small that it cannot be detected experimentally.…”

“…The set-up and procedures used for the defects creation and measurements of thermally stimulated and optically stimulated luminescence characteristics were the same as in [5]. The experiments under the uniaxial stress were carried out with the use of the special helium cryostat described in [6].…”

“…The uniaxial stress stimulates the self-trapping of electronic excitations, which leads to the change in the distribution of defects in the crystal lattice, and influences the energy barriers between different exciton configurations [5,6,10,11]. Therefore it was interesting to study the influence of the uniaxial stress on the optically and thermally stimulated exciton luminescence of CsI : Pb.…”

Spectral-kinetic luminescent characteristics of CsI-Ba single crystals

“…At room temperature in a CsI crystal the fast luminescence (305 nm) is observed that is efficiently excited by light quanta with energy more than 30 eV 1, that is an essential factor for the production of high‐energy radiation detectors 2, 3. Except for the mentioned bands in CsI crystal the band with a maximum around 412 nm connected with the localization of excitons in stretched or compressed places of crystalline lattice or near aggregates of vacancies can appear 4. The position of the maximum of this luminescence band could be located in the 410–430 nm range and depends on the sample and the excitation energy.…”