Hollow Core Optical Ring Resonator Sensor, Sensing Methods, and Methods of Fabrication

• US 20070237460A1
• Filed: 04/09/2007
• Published: 10/11/2007
• Est. Priority Date: 04/07/2006
• Status: Active Grant

• Current Assignee: Hesam Oveys, Ian M. White, Xudong Fan
• Original Assignee: Hesam Oveys, Ian M. White, Xudong Fan
• Inventors: Oveys, Hesam, White, Ian M., Fan, Xudong
• Granted Patent: US 7,693,369 B2
• Time in Patent Office: Days
• US Class Current: 385/39
• CPC Class Codes: G01N 21/7746 the waveguide coupled to a cavity resonator

Abstract

The present invention is directed to hollow core optical ring resonators (HCORRs), methods of fabricating HCORRs, and methods of using HCORRs in sensing applications. In particular, the evanescent field and whispering gallery modes of the HCORRs may be used to detect a target analyte within the hollow core of the HCORR. Other features of the present invention include utilizing the HCORR as part of a multiplex sensing device, including using the HCORR in capillary electrophoresis and chromatography applications.

Claims

1. A hollow core optical ring resonator comprising:

(a) an optical tube with an outer surface and an inner surface, whereby the inner surface forms a hollow core;

(b) an outer diameter of the optical tube ranging from about 10 μ

m to about 1000 μ

m; and

,

(c) a wall thickness of the optical tube ranging from about 1 μ

m to about 20 μ

m.

2. The hollow core optical ring resonator of claim 1, wherein the optical tube has an outer diameter ranging from about 30 μ

m to about 500 μ

m.

3. The hollow core optical ring resonator of claim 1, wherein the optical tube has an outer diameter ranging from about 50 μ

m to about 300 μ

m.

4. The hollow core optical ring resonator of claim 1, wherein the optical tube has a wall thickness ranging from about 1 μ

m to about 10 μ

m.

5. The hollow core optical ring resonator of claim 1, wherein the optical tube has a wall thickness ranging from about 2 μ

m to about 5 μ

m.

6. The hollow core optical ring resonator of claim 1, wherein the outer and inner surfaces of the optical tube are smooth.

7. The hollow core optical ring resonator of claim 1, wherein the optical tube is contacted with a light source.

8. The hollow core optical ring resonator of claim 1, the optical tube formed from a composition selected from the group consisting of:

dialectric materials, glass, quartz, fused silica, borosilicate, optical plastics, polymer materials, PDMS, semiconductor materials, GaAs, InGaAs, photonic crystal structures, or any mixtures thereof.

9. The hollow core optical ring resonator of claim 1, wherein the optical tube is contacted with a fiber taper.

10. The hollow core optical ring resonator of claim 9, wherein the optical tube is transverse to the fiber taper.

11. The hollow core optical ring resonator of claim 1, further comprising:

(a) a photodetector; and

(b) a data acquisition (DAQ) card in a computer.

12. The hollow core optical ring resonator of claim 1, further comprising:

an analyte substrate that is capable of binding a target analyte, wherein the analyte substrate is located within a fluidic channel formed by the inner surface of the optical tube.

13. The hollow core optical ring resonator sensing architecture of claim 12, wherein the analyte substrate is affixed to the inner surface of the optical tube.

14. The hollow core optical ring resonator of claim 1, wherein the optical tube is part of a multiplex device.

15. The hollow core optical ring resonator of claim 1, wherein the optical tube is part of a chromatography device.

16. The hollow core optical ring resonator of claim 1, further comprising a voltage source associated with a capillary electrophoresis device

17. A hollow core optical ring resonator sensing architecture comprising:

(a) an optical tube with a hollow core, with the optical tube having an outer diameter ranging from about 10 μ

m to about 1000 μ

m and a wall thickness ranging from about 1 μ

m to about 20 μ

m;

(b) a guided light source in contact with the optical tube of (a), wherein the light source produces an optical signal in the optical tube, the optical signal comprising whispering gallery modes and an associated evanescent field; and

(c) an optical signal that in communication with the interior of the hollow core, wherein the presence of a target analyte in the hollow core will cause modulations in the optical signal; and

(d) a photodetector that is in contact with the resulting optical signal.

18. The hollow core optical ring resonator sensing architecture of claim 17, wherein an optical tube with a hollow core is associated with another optical tube with a hollow core as part of a multiplex device, and at some point the optical tubes are separated by at least about 100 μ

m.

19. A method of fabricating a hollow core optical ring comprising:

(a) mechanically pulling an optical tube under high temperature, thereby producing an optical tube with an outer diameter ranging from about 10 μ

m to about 1000 μ

m; and

,

(b) etching a surface of the optical tube with a solution comprising acids, thereby producing a wall thickness ranging from about 1 μ

m to about 20 μ

m.

20. A method of fabricating a hollow core optical ring comprising:

(a) mechanically pulling an optical tube under high temperature, thereby producing an optical tube with an outer diameter ranging from about 10 μ

m to about 1000 μ

m; and

(b) ablating a surface of the optical tube with a laser, thereby producing a wall thickness ranging from about 1 μ

m to about 20 μ

m.

21. A method of fabricating a hollow core optical ring resonator comprising:

laser ablating an optical material, chemical etching an optical tube, pulling an optical tube with a draw tower, injecting optical polymers into a tube molding, forming photonic crystals into annular layers, fusing optical materials to form optical tubes, or any combination thereof.

22. A method of fabricating a hollow core optical ring resonator comprising the following steps:

(a) pre-etching a provided optical tube with a hollow core by submerging said tube into a pre-etching solution to produce a pre-etched tube with a reduced outer diameter;

(b) pulling the pre-etched tube at one or both ends, while heating the pre-etched tube to produce an elongated tube;

(c) post-etching the elongated tube by running a post-etching solution into the hollow core of the elongated tube to produce the optical sensor with desired wall thickness.

23. A method of detecting a target analyte comprising the following steps:

(a) contacting a test sample to the inner surface of an optical tube with a hollow core, with the optical tube having an outer diameter ranging from about 10 μ

m to about 1000 μ

m and a wall thickness ranging from about 1 μ

m to about 20 μ

m;

(b) contacting a light of a known wavelength to the optical tube with a hollow core, thereby producing an associated evanescent field which is capable of extending into the hollow core, and an associated whispering gallery mode that is measurable as an optical signal output;

(c) measuring the optical signal output; and

,

(d) detecting the presence of a target analyte in the test sample by comparing the optical signal output and the guided light input.

24. A hollow core optical ring resonator sensor system comprising:

(a) an optical tube with a hollow core, with the optical tube having an outer diameter ranging from about 10 μ

m to about 1000 μ

m and a wall thickness ranging from about 1 μ

m to about 20 μ

m;

(b) a light source capable of emitting light at a single wavelength or plurality of wavelengths, wherein the light source is positioned to emit light into the optical tube, the optical tube emitting at least a portion of the light therefrom, and

(c) a detector detecting the light emitted from the optical tube.