Fabrication of a scintillator material of elpasolite type
The present disclosure relates to a process for fabricating a crystalline scintillator material with a structure of elpasolite type of theoretical composition A 2 BC (1-y) M y X (6-y) wherein: A is chosen from among Cs, Rb, K, Na; B is chosen from among Li, K, Na; C is chosen from among the rare earths, Al, Ga; M is chosen from among the alkaline earths, X is chosen from among F, Cl, Br, I; y representing the atomic fraction of substitution of C by M and being in the range extending from 0 to 0.05, comprising its crystallization by cooling from a melt bath comprising r moles of A and s moles of B, the melt bath in contact with the material containing A and B in such a way that 2s/r is above 1. The process shows an improved fabrication yield. Moreover, the crystals obtained can have compositions closer to stoichiometry and have improved scintillation properties.
1. A detector, comprising a scintillator including a crystalline scintillator material, wherein the crystalline scintillator material:
has a theoretical formula of A 2 BC (1-y) M y X (6-y) ; and
has a real formula of A a B b C c M m X x , wherein
A comprises Cs, Rb, or a combination thereof;
B comprises Li;
C comprises a rare earth element;
M comprises an alkaline earth element; and
X comprises a halogen,
y representing an atomic fraction of substitution of C by M and being in a range extending from 0 to 0.05, a, b, c, m, and x representing respective atomic fractions of A, B, C, M, and X, a 2b/a ratio being in a range extending from 0.97 to 1.4,
wherein:
the theoretical formula is different from the real formula; and
the crystalline scintillator material is optionally doped with a scintillation activation element.
2. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Cs 2 LiYCl 6 and is optionally doped with Ce.
3. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Cs 2 LiLaBr 6(1-z) Cl 6z and is optionally doped with Ce, wherein z is from 0 to 1.
4. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Cs 2 LiYBr 6 and is optionally doped with Ce.
5. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Cs 2 LiYF 6 and is optionally doped with Ce.
6. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Cs 2(1-z) Rb 2z LiCX 6 and is optionally doped with Ce, wherein z is from 0 to 1.
7. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Rb 2 LiYX 6 and is optionally doped with Ce.
8. The detector of claim 1 , wherein the crystalline scintillator material has a theoretical formula of Cs 2(1-z) Rb 2z LiCI 6 and is optionally doped with Ce, wherein z is from 0 to 1.
9. The detector of claim 1 , wherein the crystalline scintillator material is monocrystalline.
10. The detector of claim 1 , wherein the 2b/a ratio is in the range extending from 1.1 to 1.4.
11. The detector of claim 1 , further comprising a photomultiplier tube, a photodiode, a silicon photomultiplier, or an avalanche photodiode.
12. A crystalline scintillator material, wherein the crystalline scintillator material:
has a theoretical formula of A 2 BC (1-y) M y X (6-y) ; and
has a real formula of A a B b C c M m X x , wherein
A comprises Cs, Rb, or a combination thereof;
B comprises Li;
C comprises a rare earth element;
M comprises an alkaline earth element; and
X comprises a halogen,
y representing an atomic fraction of substitution of C by M and being in a range extending from 0 to 0.05, a, b, c, m, and x representing respective atomic fractions of A, B, C, M, and X, a 2b/a ratio being in a range extending from 0.97 to 1.4,
wherein:
the theoretical formula is different from the real formula; and
the crystalline scintillator material is optionally doped with a scintillation activating element.
13. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Cs 2 LiYCl 6 , and the crystalline scintillator material is optionally doped with Ce.
14. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Cs 2 LiLaBr 6(1-z) Cl 6z , z is from 0 to 1,and the crystalline scintillator material is optionally doped with Ce.
15. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Cs 2 LiYBr 6 and is optionally doped with Ce.
16. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Cs 2 LiYF 6 , and the crystalline scintillator material is optionally doped with Ce.
17. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Cs 2(1-z) Rb 2z LiCX 6 and is optionally doped with Ce, wherein z is from 0 to 1.
18. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Rb 2 LiYX 6 and is optionally doped with Ce.
19. The crystalline scintillator material of claim 12 , wherein the theoretical formula is Cs 2(1-z) Rb 2z LiCI 6 and is optionally doped with Ce, wherein z is from 0 to 1.
20. The crystalline scintillator material of claim 12 , wherein the crystalline scintillator material has a scintillation energy resolution below 6%, measured with a source of 137Cs gamma rays of 12 keV.