Distributed feedback broad area lasers with multiple epitaxially stacked active regions and tunnel junctions

Abstract

Distributed feedback (DFB) broad area (BA) lasers with multiple epitaxially stacked active regions and tunnel junctions designed for emission around 900 nm are investigated. DFB BA lasers with a cavity length of 1 mm and different stripe widths are compared in terms of their electro-optical performance and beam quality. The laser with a 200 µm stripe width achieved a high optical pulse power of 100 W in 10 ns long pulses at an injection current of 63 A, resulting in a brightness of 81 MW/cm2sr. The optical spectrum of both lasers is centered at around 886 nm, exhibiting a narrow spectral bandwidth of 0.2 nm (64 pm/K).