Structural design of 808 nm InGaAlAs vertical-cavity surface-emitting laser

A vertical-cavity surface-emitting laser (VCSEL) was structurally designed for emitting at 808 nm. Based on a comprehensive model, the composition and width of the compressively strained In_1-x-yGa_xAl_yAs quantum well (QW) was determined. Using transmission matrix method, the spectral reflectance of distributed Bragg reflector (DBR) was plotted, and the pairs of the DBR were ascertained. The numerical simulation showed that the lasing wavelength of the In_0.14Ga_0.74Al_0.12 As/Al_0.3Ga_0.7As QW with the width of 6 nm is near 800 nm at room temperature. At the operating temperature, the material peak gain reaches 4000 cm^-1. In addition, the designed Al_0.9Ga_0.1As/Al_0.2Ga_0.8As DBR is gradient, and the thickness of the gradient layer is 20 nm. The p-DBR has 23 pairs with a reflectance of 99.57%, and the n-DBR has 39.5 pairs with a reflectance of 99.94%. Furthermore, the central wavelength of the spectrum is just at 800 nm obtained by photonic integrated circuit simulator in 3D (PICS3D) at room temperature, which agrees well with the design.