90% coupling of top surface emitting GaAs/AlGaAs quantum well laser output into 8 [micro sign]m diameter core silica fibre

Abstract

Top surface emitting GaAs/AIGaAs quantum well lasers were fabricated to exhibit stable single longitudinal and two-dimensional Gaussian-like transverse mode emission characteristics under room temperature continuous wave operation with threshold currents of less than 3 mA. Efficient coupling of laser outputs to 8 µm diameter core silica fibres was achieved through butt-coupling with coupling coefficients of 90% and 50% for fibres with etched lens-like end and flat cleaved end, respectively.