Distributed reflector laser
View Patent ↗A distributed reflector (DR) laser may include a distributed feedback (DFB) region and a distributed Bragg reflector (DBR). The DFB region may have a length in a range from 30 micrometers (μm) to 100 μm and may include a DFB grating with a first kappa in a range from 100 cm −1 to 150 cm −1 . The DBR region may be coupled end to end with the DFB region and may have a length in a range from 30-300 μm. The DBR region may include a DBR grating with a second kappa in a range from 150 cm −1 to 200 cm −1 . The DR laser may additionally include a lasing mode and a p-p resonance frequency. The lasing mode may be at a long wavelength side of a peak of a DBR reflection profile of the DBR region. The p-p resonance frequency may be less than or equal to 70 GHz.
1. A distributed reflector (DR) laser, comprising:
a distributed feedback (DFB) region having a length in a range from 30 micrometers (μm) to 100 μm and comprising a DFB grating with a first kappa in a range from 100 cm −1 to 180 cm −1 ;
a distributed Bragg reflector (DBR) region coupled end to end with the DFB region, having a length in a range from 30-300 μm and comprising a DBR grating with a second kappa in a range from 100 cm −1 to 200 cm −1 ;
a lasing mode at a long wavelength side of a peak of a DBR reflection profile of the DBR region;
a p-p resonance frequency in a range from 50-60 gigahertz (GHz); and
an intrinsic resonant frequency (Fr) in a range from 15-38 GHz.
2. The DR laser of claim 1 , wherein the length of the DFB region is 50 μm, the first kappa of the DFB grating is 120 cm −1 , the length of the DBR region is 200 μm, and the second kappa of the DBR grating is 180 cm −1 .
3. The DR laser of claim 1 , wherein the DFB region has a first stop-band that is wider than a second stop-band of the DBR region.
4. The DR laser of claim 3 , wherein the first stop-band of the DFB region is 8 nanometers (nm) in width and the second stop-band of the DBR region is 5 nm in width.
5. The DR laser of claim 1 , wherein the DFB region further comprises a multiple quantum well (MQW) structure having a large linewidth enhancement factor ax.
6. The DR laser of claim 5 , wherein the linewidth enhancement factor an of the MQW structure is greater than or equal to 4.
7. The DR laser of claim 6 , wherein the linewidth enhancement factor an of the MQW structure is greater than or equal to 8.
8. The DR laser of claim 1 , wherein the DFB region has a backside and a front side, the front side of the DFB region being coupled to the DBR region, the DR laser further comprising a high reflection (HR) coating formed on the backside of the DFB region.
9. The DR laser of claim 1 , wherein the DR laser has a 3-decibel (dB) modulation bandwidth (BW) of at least 50 gigahertz (GHz).
10. A distributed reflector (DR) laser, comprising:
a distributed feedback (DFB) region having a length in a range from 30 micrometers (μm) to 100 μm and comprising a DFB grating with a first kappa in a range from 100 cm −1 to 150 cm −1 ;
a distributed Bragg reflector (DBR) region coupled end to end with the DFB region, having a length in a range from 30-300 μm and comprising a DBR grating with a second kappa in a range from 150 cm −1 to 200 cm −1 ;
a lasing mode at a long wavelength side of a peak of a DBR reflection profile of the DBR region;
an external cavity mode within 1 nanometer of the lasing mode;
a p-p resonance frequency in a range from 50-60 gigahertz (GHz);
an intrinsic resonant frequency (Fr) in a range from 30-35 GHz; and
a 3-decibel (dB) modulation bandwidth (BW) of at least 50 gigahertz (GHz).
11. The DR laser of claim 10 , wherein the length of the DFB region is 50 μm, the first kappa of the DFB grating is 120 cm −1 , the length of the DBR region is 200 μm, and the second kappa of the DBR grating is 180 cm −1 .
12. The DR laser of claim 10 , wherein the DFB region has a first stop-band that is wider than a second stop-band of the DBR region.
13. The DR laser of claim 12 , wherein the first stop-band of the DFB region is 8 nanometers (nm) in width and the second stop-band of the DBR region is 5 nm in width.
14. The DR laser of claim 10 , wherein the external cavity mode is near a first null to the long wavelength side of the peak of the DBR reflection profile of the DBR region.
15. The DR laser of claim 10 , wherein the external cavity mode is less than or equal to 70 gigahertz (GHz) from the lasing mode.
16. The DR laser of claim 10 , wherein the DFB region further comprises a multiple quantum well (MQW) structure having a large linewidth enhancement factor an.
17. The DR laser of claim 16 , wherein the linewidth enhancement factor an of the MQW structure is greater than or equal to 4.
18. The DR laser of claim 10 , wherein the DFB region has a backside and a front side, the front side of the DFB region being coupled to the DBR region, the DR laser further comprising a high reflection (HR) coating formed on the backside of the DFB region.
19. A distributed reflector (DR) laser, comprising:
a distributed feedback (DFB) region having a length in a range from 30 micrometers (μm) to 100 μm and comprising a DFB grating with a first kappa in a range from 100 cm −1 to 180 cm −1 ;
a distributed Bragg reflector (DBR) region coupled end to end with the DFB region, having a length in a range from 30-300 μm and comprising a DBR grating with a second kappa in a range from 100 cm −1 to 200 cm −1 ;
a lasing mode at a long wavelength side of a peak of a DBR reflection profile of the DBR region; wherein the lasing mode changes frequency toward the peak of the DBR reflection profile in response to a change in electrical current in the DFB region; and
an external cavity mode within 1 nanometer of the lasing mode.