Level location and spectroscopy of , , , and in

Luminescence of LaBr3: Ce,Hf crystals under photon excitation in the ultraviolet, vacuum ultraviolet, and X-ray ranges

“…1). The spectra contain overlap ping bands at 356 and 382 nm, which are formed by typical radiative d f transitions in the Ce 3+ ion [1,5,6]. The XL efficiency of the Hf doped crystals remains almost unchanged.…”

“…An additional broad band with the maximum at 450 nm with the microsecond PL decay kinetics appears at low temperatures (T < 100 K). According to [5], this band is formed by the STE radiation. The PL spectra depend substantially on the excitation energy E exc .…”

“…Owing to the high energy resolution and good radiation resistance, these crystals can be used in spectrometry and various medical applications [1][2][3]. The mechanism of the formation of scintillation pulses in these crystals has been studied in sufficient detail due to investigations of the luminescence under excitation of different types, as well as due to research in electronic excitation energy transfer to Ce 3+ impu rity centers [4][5][6][7]. At present, the main problem is to investigate the energy nonproportionality of the light yield in the gamma ray spectral range and, especially, in the X ray region of the spectrum [8,9].…”

“…In [8], this dependence was studied using synchrotron radiation (SR) in the X ray spectral range (1.4-100 keV). The d f photoluminescence (PL) of Ce 3+ ions and self trapped excitons (STEs) in LaBr 3 : Ce under photon excitation in the ultraviolet (UV) and vacuum ultravi olet (VUV) ranges was investigated only in [4,5]. For LaBr 3 , the authors of these works gave approximate estimates for the energy of the fundamental absorption edge E fa = 5.2 eV, the energy of the exciton states of 5.4 eV, and the minimum energy of interband transi tions E g = 5.9 eV at T = 10 K. In more recent works, this result, presented in [4,5], was constantly cited, although, subsequently, such studies of LaBr 3 crystals in the VUV range have not been performed and the obtained result is clearly ambiguous.…”

Scintillation Properties and Electronic Structures of the Intrinsic and Extrinsic Mixed ElpasolitesCs2NaRBr3I3Wei1, Du2, Stand3 et al. 2016Phys. Rev. Applied25060View full textAdd to dashboardCite

“…Compared with the extrinsic Cs2NaLaBr3I3, this excitation band is much stronger in intrinsic Cs2NaLaBr3I3. It is ascribed to an exciton excitation band located slightly below the conduction band for electrons [56]. The ionized electron is not free to move and could not reach the conduction band.…”