| 1. |
- Omelkov, S. I., et al.
(författare)
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Recent advances in time-resolved luminescence spectroscopy at MAX IV and PETRA III storage rings
- 2022. - 1
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 2380
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Konferensbidrag (refereegranskat)abstract
- Short-wavelength synchrotron radiation excitation has been an indispensable tool in the studies of the properties of wide gap materials using time-resolved low-temperature luminescence spectroscopy. In recent years, several setups for such investigations have been launched at MAX IV Laboratory and Photon Science at DESY. Two permanently stationed time-resolved luminescence setups at FinEstBeAMS and P66 beamlines are in operation at MAX IV 1.5 GeV and Petra III storage rings, respectively. Mobile luminescence setups have been developed for studies at FemtoMAX and P23 beamlines. FinEstBeAMS, P66 and P23 provide time resolution from ?1/4160 to 100 ps. The FemtoMAX photon source based on an in-vacuum undulator getting an electron beam from the 3 GeV linear accelerator provides an exceptional time resolution of ?1/430 ps, limited by time response of the photodetector. The performance of the setups, achieved milestones and research challenges are discussed for four new luminescence stations available for the research community with the main focus on time-resolved techniques.
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| 2. |
- Romet, I., et al.
(författare)
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Interconfigurational d-f luminescence of Pr3+ ions in praseodymium doped Li6Y(BO3)3 single crystals
- 2024
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Ingår i: Journal of Luminescence. - 0022-2313. ; 265
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Tidskriftsartikel (refereegranskat)abstract
- Luminescence properties of undoped Li6Y(BO3)3 (LYB) crystals grown by the Bridgman method as well as undoped and praseodymium doped LYB crystals grown by the Czochralski method were studied under excitation by ultraviolet light, synchrotron radiation and electron beam in the temperature region of 5–300 K. The emission bands peaking at 4.8, 3.76 and 2.95 eV were found in undoped Czochralski-grown crystals, while the band at 3.34 eV was dominant in the Bridgman-grown crystals. These bands are presumably ascribed to excitons localized at regular and defect-perturbed lattice sites. Intense emission bands peaking at 4.75, 4.50, 4.17 and 3.98 eV were discovered in Pr doped crystals at low temperatures and related to the interconfigurational 4f15d1 → 4f2 radiative transitions in Pr3+ ions. The structure of the emission spectrum is shown to be determined by the 3H4, 3H5, 3H6, 3F2, 3F3, 3F4 terms of the Pr3+ ion. The characteristic decay time of the 4f15d1 → 4f2 emission is τ = 24 ns at low temperatures, however, it shortens to 9 ns by room temperature due to a strong thermal quenching. The study of glow curves and spectra of thermostimulated luminescence in Li6Y(BO3)3:Pr crystal irradiated by 10-keV electron beam shows that Pr3+ ions do not participate in an electron-hole recombination process.
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