Short gain cavity distributed bragg reflector laser
View Patent ↗A long wavelength, short cavity laser can include: an active region or gain cavity having a length from about 10 microns to about 150 microns; a gap region adjacent to the active region and having a gap length that is less than 30 microns or less than the length of the active region; and a distributed Bragg reflector (“DBR”) region having a grating with a kappa of at least about 200 cm −1 , wherein the gap region is between the active region and the DBR region, and wherein the laser lases at a long wavelength side of a Bragg peak of the laser. The laser can have a second DBR region opposite of the first DBR region.
1. A single mode laser comprising:
a gain cavity having a length from about 10 microns to about 150 microns;
a distributed Bragg reflector (“DBR”) region having a grating with a corrugation depth kappa of at least about 200 cm −1 ;
a gap region between the gain cavity and DBR region having a gap length that is less than about 30 microns; and
a single lasing mode at a long wavelength side of a Bragg peak of the DBR region.
2. The laser of claim 1 , wherein the lasing on the long wavelength side of the Bragg peak results from a detune of from about −2 to about −3 nm.
3. The laser of claim 1 , wherein the gain cavity has a length of less than or about 50 microns and is devoid of a grating.
4. The laser of claim 1 , comprising:
the DBR region having a length of greater than 150 microns; and
a second DBR region adjacent to the gain cavity and opposite of the DBR region, wherein the second DBR region has a length from about 40 microns to about 120 microns and a kappa ranging from 50 cm−1 when the length is about 120 microns to about 200 cm−1 when the length is about 40 microns.
5. The laser of claim 1 , wherein the gain cavity is between about 15 and about 100 microns.
6. The laser of claim 1 , wherein the gain cavity is between about 20 and about 75 microns.
7. The laser of claim 1 , the DBR region having a length of greater than 150 microns; and
a second DBR region adjacent to the gain cavity and opposite of the DBR region, wherein the second DBR region has a length and kappa both being less than the length and kappa of the first DBR region.
8. The laser of claim 7 , wherein the active region includes a corrugation depth kappa.
9. The laser of claim 8 , wherein the kappa of the active region is the same as the kappa for the first DBR region.
10. The laser of claim 8 , wherein the active region has between 10 to 20 quantum wells.
11. The laser of claim 7 , comprising detuning between the first DBR region and second DBR region.
12. The laser of claim 7 , wherein the kappa of the active region is phase shifted.
13. The laser of claim 12 , wherein the kappa of the active region is ¼ shifted.
14. The laser of claim 1 , the gap having an isolation structure with about 50 mega ohm insulation.
15. A method of designing a single mode laser, comprising:
determining a gain cavity to have a length of less than or about 150 microns;
determining a distributed Bragg reflector (“DBR”) region to have a grating with a corrugation depth kappa of at least about 200 cm −1 ;
determining a gap region between the gain cavity and DBR region having a gap length that is less than about 30 microns; and
determining a single lasing mode at a long wavelength side of a Bragg peak of the DBR region.
16. The method of claim 15 , comprising configuring the lasing mode to be on long wavelength side of the Bragg peak utilizing a detune loading effect.
17. The method of claim 16 , comprising determining the laser to have one or more of the following parameters:
gain cavity has a length of less than or about 50 microns and is devoid of a grating;
the kappa is at least about 200 cm −1 ;
a reflective fact having at least about 95% reflectivity adjacent to the gain cavity and opposite of the DBR region or a second DBR region adjacent to the gain cavity and opposite of the DBR region;
an open eye at about 10 Gb with 3.5 mA bias current and 4 mApp modulation current;
about 25 GHz bandwidth;
power for lasing is less than about 1.5 W;
modulation voltage is less than about 6 Vpp;
speed of at least about 25 Gbps;
stop band width of about 5 nm;
linewidth of below about 400 KHz;
side mode suppression ratio of about 68 dB; or
a L-I curve that is superlinear with a mode hop at about 45 mA.
18. The method of claim 16 , comprising determining the laser to have the following parameters:
the DBR region having a length of greater than 150 microns; and
a second DBR region adjacent to the gain cavity and opposite of the DBR region, wherein the second DBR region has a length from about 40 microns to about 120 microns and a kappa ranging from 50 cm−1 when the length is about 120 microns to about 200 cm−1 when the length is about 40 microns.
19. The method of claim 15 , comprising determining an insolation structure for the gap to have about 50 mega ohm insulation.
20. A method of manufacturing a single mode laser, comprising:
preparing a gain cavity to have a length of less than or about 150 microns;
preparing a distributed Bragg reflector (“DBR”) region to have a grating with a corrugation depth kappa of at least about 200 cm −1 ;
preparing a gap region between the gain cavity and DBR region having a gap length that is less than about 30 microns; and
tuning a single lasing mode at a long wavelength side of a Bragg peak of the DBR region.
21. The method of claim 20 , comprising tuning the lasing mode to be on long wavelength side of the Bragg peak utilizing a detune loading effect.
22. The method of claim 21 , comprising preparing the laser to have one or more of the following parameters:
gain cavity has a length of less than or about 50 microns and is devoid of a grating;
a gap region between the gain cavity and DBR region having a gap length that is less than about 30 microns or a gap region adjacent to the gain cavity having a gap length that is less than the length of the gain cavity;
the kappa is at least about 200 cm −1 ;
a reflective fact having at least about 95% reflectivity adjacent to the gain cavity and opposite of the DBR region or a second DBR region adjacent to the gain cavity and opposite of the DBR region;
an open eye at about 10 Gb with 3.5 mA bias current and 4 mApp modulation current;
about 25 GHz bandwidth;
power for lasing is less than about 1.5 W; modulation voltage is less than about 6 Vpp;
speed of at least about 25 Gbps;
stop band width of about 5 nm;
linewidth of below about 400 KHz;
side mode suppression ratio of about 68 dB; or
a L-I curve that is superlinear with a mode hop at about 45 mA.
23. The method of claim 21 , comprising preparing the laser to have the following parameters:
the DBR region having a length of greater than 150 microns; and
a second DBR region adjacent to the gain cavity and opposite of the DBR region, wherein the second DBR region has a length from about 40 microns to about 120 microns and a kappa ranging from 50 cm−1 when the length is about 120 microns to about 200 cm−1 when the length is about 40 microns.
24. The method of claim 20 , comprising forming an insolation structure in the gap to have about 50 mega ohm insulation.