InAs/InP quantum dot VECSEL emitting at 1.5 mu m

A high-power InAs quantum dot (QD) vertical-external-cavity surface-emitting laser emitting at 1.5 mu m is reported. The active region employs 20 layers of high-density Stranski-Krastanow InAs quantum dots on an InP substrate. The QD density and emission wavelength were independently adjusted by employing a double-cap growth sequence. Optimization of the spacer layer thickness and strain compensation rendered possible nucleation of a relatively high number of QD layers per antinode of the electromagnetic standing wave, which in turn enabled a high output power continuous wave operation of about 2.2 W. The operation wavelength could be tuned over 60 nm, taking advantage of the broadband gain characteristic of QD media. Published under license by AIP Publishing