Full text loading...
Schematic drawing of a IV-VI-on-Si VECSEL with optical pumping, (a) unstructured active layer, (b) mesa etched active layer.
Material threshold gain vs. temperature rise (maximum value at device center). The actual anti-guiding effect is compared with the guiding that holds for III-V materials, by just assuming the same structure (Fig. 1(a) ) with an opposite sign of dn/dT. The negative temperature dependence of n for IV-VI materials results in higher gth compared to III-V VECSEL.
Calculated threshold gain by VELM (black symbols) and experimental threshold power values (green symbol) vs. mesa diameter. The values without any mesa-structuring are also included—for comparison on another scale on the right.
Spectra around 3.3 μm wavelength of the VECSELs. One mode only is emitted from a VECSEL with mesa-structured active layer (experimental line width ∼1 nm), while additional transverse modes are found in the device without structuring.
Article metrics loading...