Rare-earth-doped optical fiber having small numerical aperture
AssigneeDraka Comteq B.V.
InventorsDavid Boivin, Alain Pastouret, Ekaterina Burov, Cedric Gonnet
Life of this patent
Estimating the term…
Abstract
The present invention embraces an amplifying optical fiber having a central core adapted to convey and amplify an optical signal and a cladding that surrounds the central core to confine the optical signal conveyed in the central core. The central core is formed of a core matrix in which nanoparticles are present. The nanoparticles themselves include a nanoparticle matrix and rare-earth-dopant elements. The core matrix may also include one or more additional dopants (i.e., in addition to nanoparticles). The amplifying optical fiber possesses a small numerical aperture and is suitable for use in high-pump-power applications without a degraded gain shape.
Claims25
An amplifying optical fiber, comprising:
- a central core comprising a core matrix, said central core adapted to transmit and amplify optical signals;
- and
- a cladding surrounding said central core and adapted to confine optical signals within said central core;
- wherein said core matrix comprises (i) additional dopant and (ii) nanoparticles formed of rare-earth-dopant elements and a nanoparticle matrix, said nanoparticle matrix comprising one or more complementary dopant elements;
- wherein, within said central core, the concentration of said additional dopant is between about 1 weight percent and 10 weight percent;
- wherein, within said central core, the concentration of said rare-earth-dopant elements is between about 200 ppm and 1000 ppm;
- wherein, within said central core, the concentration of said complementary dopant elements is between about 0.5 weight percent and 5 weight percent;
- and
- wherein the optical fiber's numerical aperture is between 0.10 and 0.18.
An amplifying optical fiber, comprising:
- a central core comprising a silica-based core matrix, said central core adapted to transmit and amplify optical signals;
- and
- a cladding surrounding said central core and adapted to confine optical signals within said central core;
- wherein said core matrix comprises additional dopant comprising germanium, fluorine, aluminum, and/or phosphorous;
- wherein said core matrix comprises nanoparticles that are formed of (i) rare-earth-dopant elements comprising erbium, thulium, and/or ytterbium, and (ii) a nanoparticle matrix comprising one or more complementary dopant elements;
- wherein, within said central core, the concentration of said additional dopant is between about 1 weight percent and 10 weight percent;
- wherein, within said central core, the concentration of said rare-earth-dopant elements is between about 200 ppm and 1000 ppm;
- wherein, within said central core, the concentration of said complementary dopant elements is between about 0.5 weight percent and 5 weight percent;
- and
- wherein the optical fiber's numerical aperture is between 0.10 and 0.18.
Dependencies are inferred from the claim text.