Role of lanthanum in thermoluminescence properties of La2xLu2(1−x)SiO5:Ce crystals
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The influence of lanthanum content on thermally stimulated luminescence properties of La2xLu2(1−x)SiO5:Ce (x = 0, 0.08, 0.18 and 1.50 at.%) crystals was investigated. Trapping parameters such as electron trap depth Et and electron traps content n 0 were fitted with general order kinetic function. According to the results of the VUV transmittance spectra and band gap calculation which based on the density functional theory with the generalized gradient approximation of Perdew–Burke–Ernzerhof (GGA–PBE), band structure of the crystals and recombination mechanisms of released electrons were further studied. Results showed that there were mainly two kinds of electron traps, namely shallow (Et ≈ 0.2 eV) and deep (Et ≈ 1.0 eV) traps. With the increasing of La content, the concentration of deep traps was obviously depressed, and the depth of deep traps decreased at the same time, which was explained by suggesting the downward shift of the bottom of conduction band.
The authors would like to thank Prof. Guohao Ren and Prof. Jiang Li in Shanghai Institute of Ceramics, CAS for the help in the TSL measurements. The authors thank beam line 4B8 of Beijing Synchrotron Radiation Facility for providing the beam time. This work was supported by National Natural Science Foundation of China (Grant No. 11475241) and Science and Technology Commission of Shanghai Municipality (Grant No. 15DZ2251200).
- 2.Melcher CL (1990) Lutetium orthosilicate single crystal scintillator detector, U.S. Patent No. 4,958,080Google Scholar
- 6.Dean JA (1999) Lange’s handbook of chemistry version 15th, section 4 (properties of atoms, radicals, and bonds). McGraw-Hill Inc, New YorkGoogle Scholar
- 15.Starzhinsky NG, Sidletskiy OT, Grinyov BV et al (2009) Luminescence kinetics of crystals LSO co-doped with rare-earth elements. Funct Mater 16:431Google Scholar
- 17.Yu Z, Gorbenko V, Voloshinovskii A et al (2012) Luminescence of lead-related centres in single crystalline films of Lu2SiO5. J Phys D Appl Phys 45:629Google Scholar