Optical feedback structures and methods of making

• US 20060114960A1
• Filed: 11/29/2005
• Published: 06/01/2006
• Est. Priority Date: 11/30/2004
• Status: Active Grant

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Bawendi, Moungi G., Chan, Yin Thai, Nocera, Daniel G., Snee, Preston T.
• Granted Patent: US 8,891,575 B2
• Time in Patent Office: Days
• US Class Current: 372/67
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02F 2202/36 Micro- or nanomaterials
• CPC Class Codes: H01S 3/0604 in the form of a plate or disc
• CPC Class Codes: H01S 3/0627 the resonator being monolithic, e.g. microlaser
• CPC Class Codes: H01S 5/10 Construction or shape of the optical resonator , e.g. extended or external cavity, coupled cavities, bent-guide, varying width, thickness or composition of the active region H01S5/20 takes precedence
• CPC Class Codes: H01S 5/1042 Optical microcavities, e.g. cavity dimensions comparable to the wavelength
• CPC Class Codes: H01S 5/1075 Disk lasers with special modes, e.g. whispering gallery lasers

Abstract

An optical resonator can include an optical feedback structure disposed on a substrate, and a composite including a matrix including a chromophore. The composite disposed on the substrate and in optical communication with the optical feedback structure. The chromophore can be a semiconductor nanocrystal. The resonator can provide laser emission when excited.

Claims

1. An optical resonator comprising:

a microsphere disposed on a substrate; and

a composite disposed over the microsphere and the substrate, the composite including a matrix and a chromophore.

2. The optical resonator of claim 1, wherein the microsphere has a dimension of less than 1 mm.

3. The optical resonator of claim 1, wherein the composite is adjacent to an outer surface of the microsphere.

4. The optical resonator of claim 3, wherein the composite substantially coats an outer surface of the microsphere.

5. The optical resonator of claim 1, wherein the chromophore is a semiconductor nanocrystal.

6. The optical resonator of claim 1, wherein the matrix includes silica, titania, or a mixture thereof.

7. The optical resonator of claim 1, further comprising a fluid flow path in fluid communication with the optical resonator.

8. An optical resonator comprising a substrate and a composite including a matrix and a chromophore disposed on the substrate, wherein the composite forms a grating having a periodicity selected to provide optical feedback to the chromophore.

9. The optical resonator of claim 8, wherein the chromophore is a semiconductor nanocrystal.

10. The optical resonator of claim 8, wherein the matrix includes silica, titania, or a mixture thereof.

11. The optical resonator of claim 8, further comprising a fluid flow path in fluid communication with the optical resonator.

12. A laser comprising:

a microsphere disposed on a substrate; and

a composite disposed over the microsphere and the substrate, the composite including a matrix and a chromophore; and

an excitation source configured to excite the chromophore.

13. The laser of claim 12, wherein the excitation source is a light source.

14. The laser of claim 12, wherein the microsphere has a dimension of less than 1 mm.

15. The laser of claim 12, wherein the composite is adjacent to an outer surface of the microsphere.

16. The laser of claim 15, wherein the composite substantially coats an outer surface of the microsphere.

17. The laser of claim 12, wherein the chromophore is a semiconductor nanocrystal.

18. The laser of claim 12, wherein the matrix includes silica, titania, or a mixture thereof.

19. The laser of claim 12, further comprising a fluid flow path in fluid communication with the optical resonator.

20. A laser comprising:

a substrate and a composite including a matrix and a chromophore disposed on the substrate, wherein the composite forms a grating having a periodicity selected to provide optical feedback to the chromophore; and

an excitation source configured to excite the chromophore.

21. The laser of claim 20, wherein the chromophore is a semiconductor nanocrystal.

22. The laser of claim 20, wherein the matrix includes silica, titania, or a mixture thereof.

23. The laser of claim 20, wherein the excitation source is a light source.

24. A method of making an optical resonator comprising:

arranging a microsphere on a substrate; and

depositing a composite including a matrix and a chromophore over the microsphere.

25. The method of claim 24, wherein the optical feedback structure has a dimension of less than 1 mm.

26. The method of claim 24, wherein the composite is deposited adjacent to an outer surface of the microsphere.

27. The method of claim 26, wherein the composite substantially coats an outer surface of the microsphere.

28. The method of claim 24, wherein the chromophore is a semiconductor nanocrystal.

29. The method of claim 28, wherein the semiconductor nanocrystal includes a ligand having an affinity for the matrix.

30. The method of claim 24, wherein the matrix includes silica, titania, or a mixture thereof.

31. The method of claim 24, wherein depositing the composite includes depositing a mixture including the matrix, the chromophore, and the microsphere on the substrate.

32. The method of claim 31, wherein depositing the mixture includes spin-casting the mixture.

33. A method of making an optical resonator comprising:

depositing a composite including a matrix and a chromophore on a substrate; and

shaping the composite to form a grating having a periodicity selected to provide optical feedback to the chromophore.

34. The method of claim 33, wherein shaping the composite includes contacting the composite with a patterned stamp.

35. The method of claim 33, wherein the chromophore is a semiconductor nanocrystal.

36. The method of claim 33, wherein the matrix includes silica, titania, or a mixture thereof.

37. A method of generating light comprising:

providing an optical resonator including;

a microsphere disposed on a substrate; and

a composite disposed over the microsphere and the substrate, the composite including a matrix and a chromophore; and

exciting the chromophore.

38. The method of claim 37, wherein the microsphere has a dimension of less than 1 mm.

39. The method of claim 37, wherein the chromophore is a semiconductor nanocrystal.

40. The method of claim 37, wherein the matrix includes silica, titania, or a mixture thereof.

41. A method of generating light comprising providing an optical resonator including:

a substrate and a composite including a matrix and a chromophore disposed on the substrate, wherein the composite forms a grating having a periodicity selected to provide optical feedback to the chromophore; and

exciting the chromophore.

42. The method of claim 41, wherein the chromophore is a semiconductor nanocrystal.

43. The method of claim 41, wherein the matrix includes silica, titania, or a mixture thereof.