Afterpulsing Effects in Free-Running InGaAsP Single-Photon Avalanche Diodes

We demonstrate large-area (80 mum diameter) InP-based single-photon avalanche diodes for Geiger-mode operation at 1.06 mum with dark count rates of ~1000 Hz at high detection efficiencies of 30% at 237 K, as well as simulations of dark count rate and detection efficiency that provide good agreement with measured data. Experimental results obtained using free-running operation illustrate the strong impact of afterpulsing effects for short (~200 ns) hold-off times. We present an analysis of these free-running results that quantifies the contribution of afterpulsing to the total count rate.