Optically pumpable waveguide amplifier with amplifier having tapered input and output

Patent metadata

Field	Value
Publication number	US-9929534-B2
Application number	US-201715456654-A
Country	US
Kind code	B2
Filing date	Mar 13, 2017
Priority date	Jul 25, 2013
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

Optically pumpable waveguide amplifier with amplifier having tapered input and output. The present invention provides for a optically pumpable waveguide amplification device that includes: a cladding material; a passive optical waveguide embedded in the cladding material that has no optical amplification functionality; and an active optical waveguide having an input portion, a middle portion and an output portion, including: a gain material with a higher refractive index than the passive optical waveguide, wherein the middle portion of the active optical waveguide is embedded in the cladding material, and faces the passive wave guide, such that a lower surface of the middle portion is an upper surface of the passive optical waveguide. There is also provided a device for optically pumpable waveguide amplification and a method for signal radiation amplification.

First claim

What is claimed is:

1. An optically pumpable waveguide amplifier device, comprising:
a cladding material;
a passive optical waveguide embedded in the cladding material that has no optical amplification functionality; and
an active optical waveguide having a gain material with a higher refractive index than the passive optical waveguide, and which successively includes: an input portion, a middle portion, and an output portion,
wherein the middle portion successively includes: a first taper portion, an amplifier portion, and a second taper portion; the middle portion embedded in the cladding material, and facing the passive waveguide, such that a lower surface of the middle portion is an upper surface of the passive optical waveguide; and
each of the taper portions widens towards the amplifier portion, parallel to the lower surface, such that a narrow end of each of the taper portions have a cross-sectional area that is smaller than a cross-sectional area of the passive optical waveguide at the same level of narrow end.

2. The optical waveguide amplifier device of claim 1 , wherein a width of each of the taper portions decreases non-linearly from the amplifier portion, parallel to the lower surface.

3. The optical waveguide amplifier device of claim 2 , wherein each of the taper portions decomposes into at least two sub-portions, including at least one slowly-varying sub-portion and at least one fast-varying sub-portion.

4. The optical waveguide amplifier device of claim 1 , wherein the distance between the lower surface and the upper surface is between 0.0 and 5.0 μm.

5. The optical waveguide amplifier device of claim 1 , wherein the passive optical waveguide is a rib waveguide, comprising: a slab and a strip, the strip being superimposed directly onto the slab, and wherein the upper surface of the passive optical waveguide is an upper surface of the slab, opposite to the strip with respect to the slab.

6. The optical waveguide amplifier device of claim 1 , wherein a length of the taper portions is between 50 μm and 10 mm.

7. The optical waveguide amplifier device of claim 1 , wherein a length of the amplifier portion is between 100 μm and 100.00 cm.

8. The optical waveguide amplifier device of claim 1 , wherein the gain material comprises rare-earth ions.

9. The optical waveguide amplifier device of claim 1 , wherein the gain material comprises: a dispersion of Er3+ ions.

10. The optical waveguide amplifier device of claim 1 , wherein the refractive index contrast between the passive optical waveguide and the cladding material is between 0.005 and 0.02.

11. The optical waveguide amplifier device of claim 1 , wherein the device comprises: no filter or demultiplexer to separate a pump signal from a signal to be amplified.

12. The optical waveguide amplifier device of claim 1 , wherein the passive optical waveguide comprises: two taper portions that narrow inwardly and parallel to the upper surface of the middle portion of the active optical waveguide, and wherein each taper portion faces the corresponding first taper portion and second taper portion of the middle portion in the reverse orientation.

13. The optical waveguide amplifier device of claim 12 , wherein the passive optical waveguide decomposes into two passive waveguide components, wherein the first component terminates at the narrow end of the first taper portion of the passive optical waveguide and the second component terminates at a narrow end of the second taper portion of the passive optical waveguide.

14. The optical waveguide amplifier device of claim 2 , wherein each of the taper portions decomposes into three consecutive sub-portions, comprising:
a fast-varying sub-portion;
a slowly-varying sub-portion; and
a second fast-varying sub-portion.

Assignees

• IBM

Inventors

• Raino Gabriele
• Soganci Ibrahim Murat

Classifications

• H01S3/094057

  by tapered duct or homogenized light pipe, e.g. for concentrating pump light · CPC title

• H01S3/0632

  Thin film lasers in which light propagates in the plane of the thin film · CPC title

• H01S3/1608

  erbium · CPC title

• H01S5/041

  Optical pumping · CPC title

• H01S5/34

  comprising quantum well or superlattice structures, e.g. single quantum well [SQW] lasers, multiple quantum well [MQW] lasers or graded index separate confinement heterostructure [GRINSCH] lasers (H01S5/36 takes precedence) · CPC title