OPTOELECTRONIC DEVICE AND ARRAY THEREOF

1 . An optoelectronic device comprising:

an optically active region with an electrode arrangement for applying an electric field across the optically active region;

a first curved waveguide, arranged to guide light into the optically active region; and

a second curved waveguide, arranged to guide light out of the optically active region;

wherein the first curved waveguide and the second curved waveguide are formed of a material having a different band-gap from a band-gap of the optically active region, and wherein the overall guided path formed by the first curved waveguide, the optically active region and the second curved waveguide is U-shaped.

2 . The optoelectronic device of claim 1 , wherein the first curved waveguide or the second curved waveguide are formed as regrown waveguide(s).

3 . The optoelectronic device of claim 1 ,

wherein a maximum distance between the first curved waveguide and second curved waveguide is no more than 250 μm, or,

a radius of curvature of the first curved waveguide, or,

the second curved waveguide is less than 100 μm, or,

the first curved waveguide and the second curved waveguide each curve through an angle of 90°.

4 . The optoelectronic device of claim 1 , wherein the electrode arrangement further comprises first and second electrodes, said electrodes being disposed on a first side of the optically active region and electrically connected thereto.

5 . The optoelectronic device of claim 4 , wherein the first electrode is a signal electrode and the second electrode is a ground electrode.

6 . The optoelectronic device of claim 5 , further comprising a third electrode which is a second ground electrode.

7 . The optoelectronic device of claim 4 , configured to operate as an electro-absorption modulator.

8 . The optoelectronic device of claim 1 , wherein the first curved waveguide and the second curved waveguide are low-loss passive waveguides.

9 . The optoelectronic device of claim 1 , wherein the first curved waveguide or the second curved waveguide are deep-etched waveguides.

10 . The optoelectronic device of claim 9 , wherein the deep-etched waveguides are formed of indium phosphide.

11 . The optoelectronic device of claim 1 , further comprising:

an input waveguide coupled to or provided as a continuation of the first curved waveguide; and

an output waveguide coupled to or provided as a continuation of the second curved waveguide;

wherein each of the input waveguide and the output waveguide have an end adjacent to a first edge of the optoelectronic device.

12 . The optoelectronic device of claim 11 , wherein the electrode arrangement further comprises first and second electrodes, said electrodes being disposed on a first side of the optically active region and electrically connected thereto, and the first and second electrodes are disposed adjacent to an edge of the optoelectronic device which is different to the first edge.

13 . The optoelectronic device of claim 1 , further comprising:

a distributed feedback laser, coupled to the first curved waveguide; and

an output waveguide, coupled to or provided as a continuation of the second curved waveguide;

such that the optoelectronic device is an electro-absorption modulated laser.

14 . The optoelectronic device of claim 13 ,

wherein the distributed feedback laser is formed of a material having a band-gap which is the same as the band-gap of the optically active region, or,

wherein the distributed feedback laser is formed from material having a band-gap which is different from the band-gap of the optically active region and different from the band-gap of the first and second curved waveguides.

15 . The optoelectronic device of claim 1 ,

wherein the optically active region is an electro-absorption modulator, or,

wherein the first curved waveguide and the second curved waveguide are formed of a material having a band-gap which is lower in wavelength than a band-gap of the optically active region.

16 . The optoelectronic device of claim 7 , further comprising a semiconductor optical amplifier (SOA).

17 . The optoelectronic device of claim 16 ,

wherein the SOA is located between the first curved waveguide and the second curved waveguide, or,

wherein the optoelectronic device includes an output waveguide coupled to or provided as a continuation of the second curved waveguide; and wherein the SOA is located at the output waveguide.

18 . An array of optoelectronic devices disposed on a chip, wherein:

each optoelectronic device is as set out in claim 1 ; and

a distance between optically active regions of adjacent pairs of optoelectronic devices is no more than 250 μm.

19 . The array of claim 18 , wherein each optoelectronic device has:

an input waveguide coupled to or provided as a continuation of each first curved waveguide; and

an output waveguide coupled to or provided as a continuation of each second curved waveguide;

wherein each input waveguide and each output waveguide has a first end distal to its respective optically active region, and adjacent to a same side of the chip.

20 . The array of claim 18 , wherein each optoelectronic device has:

a distributed feedback laser, coupled to each first curved waveguide; and

an output waveguide, coupled to or provided as a continuation of each second curved waveguide;

such that the optoelectronic device is an electro-absorption modulated laser;

wherein an end of each output waveguide distal to its respective optically active region is adjacent to a same side of the chip.