Size and reflectivity dependent optical loss in oxide-confined vertical-cavity surface-emitting lasers

Vertical cavity surface-emitting laser (VCSEL);Optical loss;Distributed Bragg reflector (DBR);Reflectivity

Lakomy, Katherine A ; Choquette ; Kent D.

关键词: Vertical cavity surface-emitting laser (VCSEL);    Optical loss;    Distributed Bragg reflector (DBR);    Reflectivity;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/97798/LAKOMY-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This thesis characterizes the size and mirror reflectivity dependent optical loss in 850 nm vertical cavity surface-emitting lasers (VCSELs) to optimize future VCSEL designs.A theoretical and experimental study of the excess optical loss in small diameter VCSELs with varying output coupling mirror reflectivity is presented. The size-dependent loss is measured using an optical technique where the subthreshold mode spectral splitting is input into a simple fiber wave-equation analysis to extract the imaginary component of the refractive index in the oxide aperture region, which clads the VCSEL core. In general the optical loss, as measured from the effective index confinement of the oxide aperture, increases with decreasing oxide diameter. In addition the optical loss, for the smallest oxide diameters, increases with increasing mirror reflectivity. In comparison for broad area lasers, the mirror loss will increase with decreasing mirror reflectivity. A 2-dimensional simulation of mode profiles suggests the optical loss increases as the mirror reflectivity is increased due to the longer optical path length in the higher reflectivity mirrors.