| Single mode operation in vertical cavity surface-emitting lasers is important for sensing and communications applications. A comprehensive study of the use of a periodic array of etched circular holes in the top distributed Bragg reflector of a vertical cavity surface-emitting laser to achieve single mode operation with a simple fabrication process is carried out. A theoretical analysis of photonic crystals is conducted to design devices, and the accuracy of the resulting model in predicting modal characteristics is studied experimentally. The oxide aperture size is optimized to give maximum output power and lower threshold current, the role of loss in improving modal properties is investigated, and high speed operation is characterized. Optimized lasers exhibit sub-milliamp threshold current and operate in the fundamental lateral mode for all currents. |
