Coupling system to a microsphere cavity

• US 20030012504A1
• Filed: 05/17/2002
• Published: 01/16/2003
• Est. Priority Date: 02/10/2000
• Status: Active Grant

• Current Assignee: California Institute of Technology
• Original Assignee: California Institute of Technology
• Inventors: Iltchenko, Vladimir
• Granted Patent: US 6,798,947 B2
• Time in Patent Office: Days
• US Class Current: 385/39
• CPC Class Codes: G02B 2006/12104 Mirror; Reflectors or the like
• CPC Class Codes: G02B 6/10 of the optical waveguide type G02B6/02, G02B6/24 take precedence; devices or arrangements for the control of light by electric, magnetic, electro-magnetic or acoustic means G02F1/00; transferring the modulation of modulated light G02F2/00; optical logic elements G02F3/00; optical analogue/digital converters G02F7/00
• CPC Class Codes: G02B 6/12007 forming wavelength selective elements, e.g. multiplexer, demultiplexer
• CPC Class Codes: G02B 6/262 Optical details of coupling light into, or out of, or between fibre ends, e.g. special fibre end shapes or associated optical elements
• CPC Class Codes: G02B 6/264 with optical elements between opposed fibre ends which perform a function other than beam splitting having lens focusing means G02B6/32; utilising prism or grating G02B6/34
• CPC Class Codes: G02B 6/29341 Loop resonators operating in a whispering gallery mode evanescently coupled to a light guide, e.g. sphere or disk or cylinder evanescent coupling for sensing fluorescence G01N21/648
• CPC Class Codes: H01S 3/0604 in the form of a plate or disc
• CPC Class Codes: H01S 3/083 Ring lasers fibre ring lasers H01S3/06791
• CPC Class Codes: H01S 5/1032 Coupling to elements comprising an optical axis that is not aligned with the optical axis of the active region
• CPC Class Codes: H01S 5/1075 Disk lasers with special modes, e.g. whispering gallery lasers

Abstract

At technique for holding a resonator relative to an optical fiber at a specified distance. Structures including a rectangular indentation may be formed in the end of the optical fiber. The resonator may be placed against edges of the structures, to hold a different portion of the resonator spaced from an area where the waveguide modes will emanate.

Claims

1. An apparatus comprising:

a fiber, having a core and a clad, and having an end portion, said end portion formed with an indentation portion with first and second opposing edges, and a lower surface portion being lower then said first and second opposing edges, and wherein said core portion of said fiber is between said first and second opposing edges.

2. An apparatus as in claim 1, wherein said indentation portion is a substantially rectangular groove.

5. An apparatus as in claim 1, wherein said end portion of said fiber is a cleaved end portion which is cleaved at a specified angle which is non 180 degrees relative to an axis of the fiber.

6. An apparatus as in claim 5, wherein said specified angle is 45 degrees.

7. An apparatus as in claim 1, further comprising a resonator, having a curved outer surface, which is pressed against both said first and second opposing edges.

8. An apparatus as in claim 7, wherein said curved outer surface is spaced by a specified amount from said lower surface portion when pressed against said first and second opposing edges.

9. An apparatus as in claim 8, wherein said specified amount is one micron.

10. An apparatus as in claim 8, wherein a minimum amount of said specified amount is at an area where said core portion is located.

11. An apparatus as in claim 1, wherein said indentation portion extends substantially from one outer edge of the fiber to the other outer edge of the fiber.

12. An apparatus as in claim 1, wherein said indentation portion extends by a specified amount on a surface of said fiber, said specified amount being less than a distance from one outer edge of the fiber to the other outer edge of the fiber.

13. An apparatus as in claim 1, further comprising a second curved surface, forming holding areas outside of said first and second opposing edges.

14. An apparatus as in claim 13, wherein said second curved surface is substantially round, and is centered around an area of said core.

15. An apparatus as in claim 13, wherein said indentation portion extends by only a specified amount over a surface on said fiber, where said specified amount is less than a distance from 1 outer edge of the fiber to the other outer edge of the fiber.

16. An apparatus as in claim 13, further comprising a resonator element with a curved outer wall, coupled to be held between surfaces of said curved outer surface.

17. An apparatus as in claim 1, further comprising a resonator element, coupled to surfaces of said fiber.

19. A method as in claim 18, wherein said edge portion of said optical fiber comprises edge portions defining a notch in the portion of the optical fiber.

20. A method as in claim 19, wherein said end portion of said optical fiber is a cleaved end portion.

21. A method as in claim 20, wherein said notch is formed by a rectangular indentation in the end of the optical fiber.

22. A method as in claim 21, further comprising conducting light to a location within said rectangular or indentation.

23. A method as in claim 21, wherein said placing comprises pressing curved surfaces of said resonator against edges of said rectangular indentation.

24. A method as in claim 23, wherein said curved surfaces of said resonator are spherical surfaces.

25. A method as in claim 18, wherein said placing comprises placing curved surfaces of a resonator against corresponding curved surfaces formed on an end of said optical fiber.

3. An apparatus as in claim l,wherein said indentation portion has substantially vertical sidewalls, and a substantially flattened bottom.

4. An apparatus as in claim 3, wherein said core is in a central portion between said substantially vertical sidewalls.

18. A method, comprising:

conducting light within an optical fiber to an edge portion of the optical fiber; and

placing a resonator within a proximity of said edge portion of said optical fiber in a way such that a portion of said resonator is pressed against first surfaces of said optical fiber, and another portion of said resonator is spaced from second surfaces of said optical fiber, said second surfaces of said optical fiber including surfaces including a core of said fiber.