3-4.5 μm continuously tunable single mode VECSEL

We present continuously tunable Vertical External Cavity Surface Emitting Lasers (VECSEL) in the mid-infrared. The structure based on IV-VI semiconductors is epitaxially grown on a Si-substrates. The VECSEL emit one single mode, which is mode hop-free tunable over 50-100nm around the center wavelength. In this work, two different devices are presented, emitting at 3.4μm and 3.9μm, respectively. The lasers operate near room temperature with thermoelectric stabilization. They are optically pumped, yielding an output power >10mWp. The axial symmetric emission beam has a half divergence angle of