Lanthanide doped strontium barium mixed halide scintillators

1. An inorganic scintillator having the formula:

Sr 1-y′-y Ba y′ X 1 x X 2 2-x :Ln y   (I);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element and are each independently Cl, Br, or I, Ln is a lanthanide with a valence of 2+, x has a value having the range 0<x≦2, y′ has a value having the range 0≦y′<1, y has a value having the range 0<y≦1, and y′+y<1; and the inorganic scintillator is a single crystal having at least one dimension of a length of at least 1 mm, or a length at least sufficient to stop or absorb gamma-radiation.

2. The inorganic scintillator of claim 1 , wherein X 1 is Br and X 2 is I.

3. The inorganic scintillator of claim 1 , wherein Ln is Eu or Yb.

4. The inorganic scintillator of claim 1 , wherein x has a value having the range 0≦x≦2.

5. The inorganic scintillator of claim 4 , wherein x has a value having the range 0.3≦x≦1.2.

6. The inorganic scintillator of claim 1 , wherein y′ has a value having the range 0≦y′≦0.85.

7. The inorganic scintillator of claim 1 , wherein y has a value having the range 0.001≦y≦0.5.

8. The inorganic scintillator of claim 2 , wherein Ln is Eu, x has a value having the range 0.3≦x≦1.2, y′ has a value having the range 0≦y′≦0.85, and y is about 0.05.

9. The inorganic scintillator of claim 1 , wherein the single crystal has at least one dimension of a length of at least 5 mm.

10. An inorganic scintillator having the formula:

Sr 1-y′-2y Ba y′ X 1 x X 2 2-x :Ln y ,M y   (II);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, M is an alkaline metal with an atomic number smaller than the atomic number of Sr or Ba, x has a value having the range 0<x<2, and y′ has a value having the range 0≦y′≦1, y has a value having the range 0<y≦0.5, and y′+2y<1; or,

Sr 1-y′-z Ba y′ X 1 x X 2 2-x :Ln z   (III);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element and are each independently Cl, Br, or I, Ln is a lanthanide with a valence of 3+, x has a value having the range 0<x<2, y′ has a value having the range 0≦y′<1, and z has a value having the range 0<z≦0.1, and y′+z<1; and

wherein the inorganic scintillator is a single crystal having at least one dimension of a length of at least 1 mm, or a length at least sufficient to stop or absorb gamma-radiation.

11. The inorganic scintillator of claim 10 , wherein X 1 is Br and X 2 is I.

12. The inorganic scintillator of claim 10 , wherein Ln is Ce.

13. The inorganic scintillator of claim 10 , wherein the inorganic scintillator has the formula (II) and M is Li or Na.

14. The inorganic scintillator of claim 10 , wherein x has a value having the range 0.3≦x≦1.2.

15. The inorganic scintillator of claim 10 , wherein y′ has a value having the range 0≦y′≦0.85.

16. The inorganic scintillator of claim 10 , wherein the inorganic scintillator has the formula (II) and y has a value having the range 0.001≦y≦0.5.

17. The inorganic scintillator of claim 10 , wherein the inorganic scintillator has the formula (III) and z has a value having the range 0.001≦z≦0.1.

18. The inorganic scintillator of claim 10 , wherein the single crystal has at least one dimension of a length of at least 5 mm.

19. The inorganic scintillator of claim 10 , wherein the inorganic scintillator has the formula:

Sr 1-y′-2y Ba y′ X 1 x X 2 2-x :Ln y ,M y   (II);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, M is an alkaline metal with an atomic number smaller than the atomic number of Sr or Ba, x has a value having the range 0<x<2, and y′ has a value having the range 0≦y′<1, y has a value having the range 0<y≦0.5, and y′+2y<1.

20. The inorganic scintillator of claim 10 , wherein the inorganic scintillator has the formula:

Sr 1-y′-z Ba y′ X 1 x X 2 2-x :Ln z   (III);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element and are each independently Cl, Br, or I, Ln is a lanthanide with a valence of 3+, x has a value having the range 0<x<2, y′ has a value having the range 0≦y′<1, and z has a value having the range 0<z≦0.1, and y′+z<1.

21. An inorganic scintillator having the formula:

Sr 1-y′-y Ba y′ X 1 x X 2 2-x :Ln y   (I);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 2+, x has a value having the range 0<x≦2, y′ has a value having the range 0<y′<1, y has a value having the range 0<y≦1, and y′+y<1;

Sr 1-y′-2y Ba y′ X 1 x X 2 2-x :Ln y ,M y   (II);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, M is an alkaline metal with an atomic number smaller than the atomic number of Sr or Ba, x has a value having the range 0<x<2, and y′ has a value having the range 0≦y′<1, y has a value having the range 0<y≦0.5, and y′+2y<1; or,

Sr 1-y′-z Ba y′ X 1 x X 2 2-x :Ln z   (III);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, x has a value having the range 0<x<2, y′ has a value having the range 0<y′<1, and z has a value having the range 0<z≦1, and y′+z<1; and

wherein the inorganic scintillator is a single crystal having at least one dimension of a length of at least 1 mm, or a length at least sufficient to stop or absorb gamma-radiation.

22. The inorganic scintillator of claim 21 , wherein the inorganic scintillator has the formula:

Sr 1-y′-y Ba y′ X 1 x X 2 2-x :Ln y   (I);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 2+, x has a value having the range 0<x≦2, y′ has a value having the range 0<y′<1, y has a value having the range 0<y≦1, and y′+y<1.

23. The inorganic scintillator of claim 21 , wherein the inorganic scintillator has the formula:

Sr 1-y′-2y Ba y′ X 1 x X 2 2-x :Ln y ,M y   (II);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, M is an alkaline metal with an atomic number smaller than the atomic number of Sr or Ba, x has a value having the range 0<x<2, and y′ has a value having the range 0≦y′<1, y has a value having the range 0<y≦0.5, and y′+2y<1.

24. The inorganic scintillator of claim 23 , wherein y′ has a value having the range 0<y′<1.

25. The inorganic scintillator of claim 21 , wherein the inorganic scintillator has the formula:

Sr 1-y′-z Ba y′ X 1 x X 2 2-x :Ln z   (III);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, x has a value having the range 0<x<2, y′ has a value having the range 0<y′<1, and z has a value having the range 0<z≦0.1, and y′+z<1.

26. A device for detecting an ionizing radiation comprising:

(a) an inorganic scintillator having the formula:

Sr 1-y′-y Ba y′ X 1 x X 2 2-x :Ln y   (I);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not same halogen element, Ln is a lanthanide with a valence of 2+, x has a value having the range 0<x≦2, y′ has a value having the range 0≦y′<1, y has a value having the range 0<y≦1, and y′+y<1;

Sr 1-y′-2y Ba y′ X 1 x X 2 2-x :Ln y ,M y   (II);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, M is an alkaline metal with an atomic number smaller than the atomic number of Sr or Ba, x has a value having the range 0<x<2, and y′ has a value having the range 0≦y′<1, y has a value having the range 0<y≦0.5, and y′+2y<1; or,

Sr 1-y′-z Ba y′ X 1 x X 2 2-x :Ln z   (III);

wherein X 1 is a first halogen element, X 2 is a second halogen element, X 1 and X 2 are not the same halogen element, Ln is a lanthanide with a valence of 3+, x has a value having the range 0<x<2, y′ has a value having the range 0≦y′<1, and z has a value having the range 0<z≦0.1, and y′+z<1; and,

wherein the inorganic scintillator is a single crystal having at least one dimension of a length of at least 1 mm, or a length at least sufficient to stop or absorb gamma-radiation; and,

(b) a photodetector optically coupled to the scintillator for producing an electrical signal in response to an emission of a light pulse by the scintillator.

27. The device according to claim 25 , wherein the photodetector is a photomultiplier, photodiode, or CCD sensor.