Optical guide comprising an amplifier medium and a method for producing said guide

• US 20030175003A1
• Filed: 03/14/2003
• Published: 09/18/2003
• Est. Priority Date: 03/18/2002
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Alcatel SA (Nokia Corporation)
• Inventors: Gasca, Laurent, Pastouret, Alain, Belouet, Christian, Moreau, Christine, Baniel, Pascal
• Granted Patent: US 7,031,590 B2
• Time in Patent Office: Days
• US Class Current: 385/142
• CPC Class Codes: C03C 13/04 Fibre optics, e.g. core and clad fibre compositions light guides G02B6/00
• CPC Class Codes: C03C 13/045 Silica-containing oxide glass compositions
• CPC Class Codes: C03C 14/004 the non-glass component being in the form of particles or flakes
• CPC Class Codes: C03C 14/006 the non-glass component being in the form of microcrystallites, e.g. of optically or electrically active material
• CPC Class Codes: C03C 2201/20 containing non-metals other than boron or halide
• CPC Class Codes: C03C 2201/28 containing phosphorus
• CPC Class Codes: C03C 2201/31 containing germanium
• CPC Class Codes: C03C 2201/32 containing aluminium C03C2201/36 takes precedence
• CPC Class Codes: C03C 2201/3411 Yttrium
• CPC Class Codes: C03C 2201/3476 Erbium
• CPC Class Codes: C03C 2201/3482 Thulium
• CPC Class Codes: C03C 2201/36 containing rare earth metals and aluminium, e.g. Er-Al co-doped
• CPC Class Codes: C03C 3/06 with more than 90% silica by weight, e.g. quartz C03C3/045 takes precedence
• CPC Class Codes: C03C 4/0071 for laserable glass
• CPC Class Codes: C03C 4/10 for infrared transmitting glass
• CPC Class Codes: H01S 3/06716 Fibre compositions per se C03C13/04or doping with active elements lasing materials in general H01S3/14
• CPC Class Codes: H01S 3/1616 thulium
• CPC Class Codes: H01S 3/169 Nanoparticles, e.g. doped nanoparticles acting as a gain material

Abstract

The present invention concerns an optical guide (100) comprising an amplifier medium including:

a core (10) in a main matrix of a transparent material, the main matrix containing particules (1, 2), each particule being formed of a submicronic matrix distinct from the main matrix and doped by an active metal element,

an external guiding cladding (11) in contact with the core (10).

The size of the particules (1, 2) is smaller than 20 nm.

The present invention also concerns a method for producing this guide.

Claims

1. Optical guide comprising an amplifier medium including

a core in a main matrix of a transparent material, the main matrix containing particles, each particle being formed of a submicronic matrix distinct from the main matrix and doped by an active metallic element,

an external guiding cladding in contact with the core,

wherein the size of the particles is smaller than 20 nm and wherein said active element is not present in the main matrix.

2. Optical guide according to claim 1, wherein the main matrix contains several types of said particles, the particles of various types being dinstinct from one another via their distinct submicronic matrix and/or by their distinct active element.

3. Optical guide according to claim 1, wherein the submicronic matrix is selected from metallic oxide-based matrices and fluoride-based, metallic oxifluoride-based, sulfur-based matrices and preferably from silicon-based matrices and matrices containing the ions La³⁺ and/or Al³⁺.

4. Optical guide according to claim 1, wherein the active metallic element is selected from the ions of rare earths and the ions of transition metals and preferably from erbium, ytterbium, thulium ions and the ions Cr⁴⁺ and Mn³⁺.

5. Optical guide accordoing to claim 1, wherein the transparent material is selected from vitreous materials and polymers and preferably from silicon glass, polycarbonates, polymethylmethacrylates and polymers containing fluorine.

6. Optical guide according to claim 1, wherein it is selected from an optical fiber and a planar guide.

7. Method for producing an optical guide comprising an amplifier medium including:

a core in a main matrix of a transparent material, the main matrix containing particles, each formed of a submicronic matrix distinct from the main matrix and doped by an active metallic element,

an external guiding cladding in contact with the core,

wherein it includes the following stages;

a stage for preparing said particles selected from chemical synthesis and laser ablation,

a stage for incorporating said particles in a precursor of the main matrix.

8. Method for producing a guide according to claim 7, wherein chemical synthesis includes a stage for producing sol-gel type organometallic precursors of said particles including the active element followed by a stage for forming organometallic droplets by vaporizing the organometallic precursors and a stage for transforming the droplets into particles by eliminating the organic elements.

9. Method for producing a guide according to claim 8, wherein the sol-gel production stage includes:

The mixing in an alcohol solvent of a compound containing the metal of the active element with sol-gel monomers each including a complexing compound linked to a first metal alkoxide,

The formation of organometallic cores by complexing the metal of the active element,

The growth of the organometallic cores in organometallic compounds by adding second metal alkoxides reacting with the first alcoxydes,

The cross-linking of the structure of said compounds via the intramolecular sol-gel reaction so as to form said organometallic precursors.

10. Method for producing a guide according to claim 9, wherein:

The first and second metal alkoxides are selected from silicon and aluminum alkoxides,

The organic complexing compound is selected from the atoms or groups of donor atoms and preferably amines, acetates, beta-diketonates, thiols and ethers.

11. Method for producing a guide according to claim 7, wherein laser ablation includes a stage for ejecting atoms by the irridiation of a target doped by said active elements selected from the composition targets approximately identical to said particles, followed by a stage for forming said particles via condensation under gas pressure of the ejected atoms.

12. Method for producing a guide according to claim 11, wherein the targets are selected from the doped metallic oxides and metallic fluorides and preferably Al₂O₃ doped by erbium ions, Sb₂O₃ doped by thulium ions, LaF₃ doped by erbium ions, Y₂O₃ doped by erbium ions and doped ZnO.

13. Method for producing a guide according to claim 7, wherein the stage for incorporating the particles is selected from a stage for impregnating said precursor of the main matrix, a stage for the chemical vapour depositing on said precursor and a mixing stage in the precursor.

14. Method for producing a guide according to claim 7, wherein it includes a stage for forming said precursor of the main matrix by depositing on at least one portion of the cladding and preferably selected from modified vapor phase depositings and depositings via centrifugal means.