Top-emitting micromechanical VCSEL with a 31.6-nm tuning range

We report a top-emitting micromechanical vertical-cavity surface-emitting laser (VCSEL) with a continuously tunable wavelength range of 31.6 nm, the widest tuning range demonstrated by a VCSEL to date. Good laser characteristics are maintained throughout the tuning range centered at 935 nm: continuous-wave (CW) threshold occurs between 1.24.5 mA while output power at 10-mA DC bias remains between 0.5 and 1.6 mW. By analyzing the pulsed differential quantum efficiency as a function of emission wavelength, we conclude that tilt loss from the cantilever design does not significantly affect the tuning range or laser performance.