US 11,837,838 B1
Laser having tapered region
Gordon Barbour Morrison, Summerland, CA (US)
Assigned to Freedom Photonics LLC, Goleta, CA (US)
Filed by Freedom Photonics LLC, Goleta, CA (US)
Filed on Jan. 29, 2021, as Appl. No. 17/163,028.
Claims priority of provisional application 62/968,966, filed on Jan. 31, 2020.
Int. Cl. H01S 5/10 (2021.01); H01S 5/125 (2006.01); H01S 5/042 (2006.01)
CPC H01S 5/1007 (2013.01) [H01S 5/04256 (2019.08); H01S 5/101 (2013.01); H01S 5/1014 (2013.01); H01S 5/1064 (2013.01); H01S 5/125 (2013.01); H01S 2301/166 (2013.01)] 29 Claims
OG exemplary drawing
 
1. A semiconductor laser comprising:
a waveguide comprising:
(i) a first waveguide region extending in a longitudinal direction between first and second ends of said first waveguide region and having a width extending in a lateral direction, said width of said first waveguide region being configured such that said first waveguide region supports a single bound transverse mode; and
(ii) a second waveguide region extending in a longitudinal direction between first and second ends of said second waveguide region and having a width extending in a lateral direction; and
first and second optical reflectors, said first and second waveguide regions disposed between said first and second optical reflectors, said first optical reflector closer to said first end of said first waveguide region than said second end of said first waveguide region, said second optical reflector closer to said second end of said second waveguide region than said first end of said second waveguide region, said first and second optical reflectors disposed with respect to each other to form a laser cavity therebetween;
wherein the width of said second waveguide region at said second end of said second waveguide region is larger than the width at said first end of said second waveguide region;
wherein at least a portion of said second waveguide region comprises a semiconductor gain material configured to provide optical gain for light propagating within said laser cavity;
wherein at least the first optical reflector comprises a distributed Bragg reflector (DBR) and is formed from a material different from the semiconductor gain material; and
wherein said second waveguide region is configured to support a plurality of bound transverse modes, and the laser cavity sustains and outputs a single transverse mode.