Oxide-apertured photodetector integrated on vertical cavity surface emitting laser

The authors have designed and fabricated oxide-apertured photodetectors integrated with vertical cavity surface emitting lasers (VCSELs). The photocurrent originating from spontaneous emission is suppressed by more than a factor of 10 in this integrated photodetector owing to the use of nonradiative recombination at the GaAs/oxide interface. In addition, the unavoidable internal loss from the detector is minimised by locating the GaAs detection layer as far as possible from the VCSEL cavity.