Abstract
InGaAs/InP-based semiconductor avalanche photodiodes are usually employed for single-photon counting at telecom wavelength. However they are affected by afterpulsing which limits the diode performance. Recently, Princeton Lightwave has commercialized a diode integrating monolithically a feedback resistor. This solution effectively quenches the avalanche and drastically reduces afterpulsing. Here, we report the development and characterization of a detector module based on this diode, implementing an active hold-off circuit which further reduces the afterpulsing and notably improves the detector performances. We demonstrate free-running operation with 600 Hz dark count rate at 10% detection efficiency. We also improved the standard double-window technique for the afterpulsing characterization. Our algorithm implemented by a FPGA allows one to put the APD in a well-defined initial condition and to measure the impact of the higher order afterpulses.
Acknowledgements
We thank S. Decadri for the work done during the electronic development. This work was supported by the Swiss National Science Foundation NCCR within the projects Quantum Photonics and QSIT, Quantum Science and Information Technology.