Continuously tunable singlemode VECSEL at 3.3μm wavelength for spectroscopy

A singlemode tunable vertical external cavity surface emitting laser (VECSEL) has been realised. The VECSEL can be tuned continuously over more than 80 nm from ~3.22 to 3.3μm wavelength. Tuning is performed by changing the cavity length with a piezoelectric driver. Covering this wavelength range allows various potential applications, especially for gas spectroscopy of organic compounds. The VECSEL is optically pumped, and emits a maximum output power of 20 mW_p when cooled with a Peltier element to -20-°C. The active medium consist of PbSe quantum wells embedded in Pb_1-xSr_xSe (x=0.08) barrier layers and is grown on a Si-substrate.