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.