Planar proton implanted VCSEL´s and fiber-coupled 2-D VCSEL arrays

Efficient planar proton implanted InGaAs-GaAs MQW vertical-cavity surface-emitting laser diodes (VCSEL´s) and 2-D arrays are fabricated using molecular beam epitaxy and p-type beryllium doping. Using single-step grading and modulation δ-doping in the p-type AlGaAs-GaAs Bragg reflectors top surface emitting devices with a maximum wall-plug efficiency of 17.6% and a threshold voltage of 1.8 V are demonstrated. Transverse mode behavior is well described in terms of Laguerre-Gaussian functions. Independently addressable 10×10 arrays of 12 μm diameter VCSEL´s exhibit electrical 3-dB modulation bandwidths up to 6 GHz. Light from the array is simultaneously launched into a 10×10 multimode fiber bundle with coupling efficiency above 70% applying a simple butt-coupling technique