183 nm tuning range in a grating-coupled external-cavity quantum dot laser

We report on the 183 nm tuning range of an anti-reflection coated quantum dot (QD) laser using a diffraction grating in an external-cavity configuration. Over this range the laser threshold current density varied between 0.25 kA/cm/sup 2/ and 2.22 kA/cm/sup 2/ with an average value of 0.84 kA/cm/sup 2/. The laser active region is composed of a single InAs quantum dot layer confined in the middle of a 10-nm thick InGaAs quantum well and sandwiched by GaAs waveguide layers.