Pr:(Lu,Y) 3 (Ga,Al) 5 O 12 single crystals were grown by the micro-pulling down ( μ-PD) method. Luminescence and scintillation properties were measured. The substitution phenomenon in the Lu 3+ sites ...with Y 3+ and Al 3+ sites with Ga 3+ in garnet structure has been studied. Pr 3+ 5d-4f emission within 300-400 nm accompanied by weak Pr 3+ 4f-4f emission in 480-650 nm were observed in Ga 0-60 at.% substituted samples. Only Pr 3+ 4f-4f emission was observed in Ga 80 at.% substituted sample. The light yield of Pr1%:Lu 2 Y 1 Ga 2 Al 2 O 12 sample was almost the same as that of Cz grown Pr:LuAG standard. Two-component scintillation decay of 17.9 ns (93%) and 68.0 ns (7%) were obtained using the PMT and digital oscilloscope TDS5032B. Slower decay components were reduced by Ga and Y substitution in LuAG structure.
Abstract
Ce-doped (Y
y
Gd
1−
y
)
3
(Ga
x
Al
1−
x
)
5
O
12
(
x
= 0, 1, 2, 3, 4 and
y
= 1, 2, 3) single crystals are grown by the micro-pulling down method. X-ray diffraction and electron probe ...microanalysis techniques are employed to check their structure and chemical composition, respectively. Optical and photoluminescence characteristics are measured and radioluminescence spectra, light yield and scintillation decay measurements are further made to evaluate the scintillation performance. We show that balanced Gd and Ga admixture in the Y
3
Al
5
O
12
structure can considerably increase the scintillation efficiency, and the spectrally corrected light yield value exceeds 44 000 photon MeV
−1
. Scintillation decay times approach that of Ce
3+
photoluminescence decay and an additional less intense slower component is also observed. Physical aspects of energy transfer process and 5d
1
excited state depopulation are discussed. The micro-pulling down technique is shown as an ideal tool for a directed combinatorial search for targeted single crystal compositions to reveal those with the highest figure-of-merit for a given application field.
Ce-doped (Y sub(y)Gd sub(1-y)) sub(3)(Ga sub(x)Al sub(1-x)) sub(5)O sub(12) (x = 0, 1, 2, 3, 4 and y = 1, 2, 3) single crystals are grown by the micro-pulling down method. X-ray diffraction and ...electron probe microanalysis techniques are employed to check their structure and chemical composition, respectively. Optical and photoluminescence characteristics are measured and radioluminescence spectra, light yield and scintillation decay measurements are further made to evaluate the scintillation performance. We show that balanced Gd and Ga admixture in the Y sub(3)Al sub(5)O sub(12) structure can considerably increase the scintillation efficiency, and the spectrally corrected light yield value exceeds 44 000 photon MeV super(-1). Scintillation decay times approach that of Ce super(3+) photoluminescence decay and an additional less intense slower component is also observed. Physical aspects of energy transfer process and 5d sub(1) excited state depopulation are discussed. The micro-pulling down technique is shown as an ideal tool for a directed combinatorial search for targeted single crystal compositions to reveal those with the highest figure-of-merit for a given application field.
Ce:(Lu,Y) 3 (Ga,Al) 5 O 12 single crystals were grown by the μ -PD method with RF heating system. In these crystals, Ce 3+ 4f-5d emission is observed within 500-530 nm wavelength. Emission peak ...shifts to shorter wavelength and the decay accelerates with increasing Ga concentration. In the case of Ce:Lu 2 Y 1 (Ga,Al) 5 O 12 series,the Ce0.2% Lu 2 Y 1 Ga 3 Al 2 O 12 crystal showed the highest emission intensity. In order to determine light yield, the energy spectra were measured under 662 keV ã-ray excitation ( 137 Cs source) and detection by an APD S8664-55(Hamamatsu). The light yield was calibrated from Fe 55 direct irradiation peak to APD. The light yield of Ce0.2%: Lu 2 Y 1 Ga 3 Al 2 O 12 sample was of about 30,000 photon/MeV. Dominant scintillation decay time was of about 50 ns.
In this report 2inch size Ce:Gd 3 Al 2 Ga 3 O 12 (Ce:GAGG) single crystals were grown by the Czhocralski (Cz) method. Luminescence and scintillation properties were measured. In order to determine ...light yield the energy spectra were collected under 662 keV γ-ray excitation( 137 Cs source) were detected by a APD S8664-55(Hamamatsu). The light yield of CeGAGG sample was calibrated from 55 Fe direct irradiation peak to APD. The light yield was around 46,000photon/MeV. Energy resolution was 4.9%@662keV by using 3×3×1mm size sample. The density of CeGAGG is theoretically 6.63 g/cm 3 . Further results will be reported in the presentation.
In this report, the Ce: (Lu,Gd) 3 (Ga,Al) 5 O 12 single crystal were grown by the micro-pulling down (m-PD) method. Luminescence and scintillation properties were measured. The substitution at the Al ...3+ sites by Ga 3+ and at the Lu 3+ sites by Gd 3+ in garnet structure has been studied. In these crystals, Ce 3+ 4f-5d emission is observed with 500-530nm wavelength. Emission peak shifts to shorter wavelength and the decay accelerates with increasing Ga concentration. In the case of Ce: Lu 2 Gd 1 (Ga,Al) 5 O 12 series, Ce: Lu 2 Gd 1 Ga 3 Al 2 O 12 shows highest emission intensity. The light yield of Ce: Lu 2 Gd 1 Ga 3 Al 2 O 12 sample with 3mmφ×1mm size was around 30,000 photon/MeV using calibration from 55 Fe direct irradiation peak to APD. Scintillation decay time was around 50ns. Density is theoretically 7.1g/cm 3 .
Pr: (Lu,Y) 3 (Ga,Al) 5 O 12 single crystals were grown by the micro-pulling down (μ-PD) method. Luminescence and scintillation properties were measured. The substitution phenomenon in the Lu 3+ sites ...with Y 3+ and Al 3+ sites with Ga 3+ in garnet structure has been studied. Pr 3+ 5d-4f emission within 300-400nm accompanied by weak Pr 3+ 4f-4f emission in 480-650nm are observed in Ga 0-60 at.% substituted samples. Ga 80 at.% substituted sample shows only Pr 3+ 4f-4f emission. The light output of Pr1%:Lu 2 Y 1 Ga 2 Al 2 O 12 sample was almost same as that of Cz grown Pr:LuAG standard. Two-component scintillation decay shows 17.9ns (93%) and 68.0ns (7%) using the PMT and digital oscilloscope TDS5032B. Slower decay components are reduced by Ga and Y substitution in LuAG structure.
