High power single-lateral-mode operation of InAs quantum dot based ridge type laser diodes by utilizing a double bend waveguide structure

We report on the high-power, single-lateral-mode operation of InAs quantum dot (QD) based ridge type laser diodes (LDs) by utilizing a double bend (DB) waveguide structure. The LDs were designed so that only fundamental modes propagate and higher optical modes are suppressed through the bent regions. DB waveguide LDs allow the use of wide ridge widths for fundamental mode operations, which helps to increase their output power via the increase in their net gain. We measured continuous wave single-lateral-mode output power of up to 310 mW from InAs QD DB waveguide LDs manufactured with 10-μm-wide stripes without facet coating.