Afterpulse background suppression in time-correlated single photon counting lifetime experiments using optimized gate filter

Using a monostable multivibrator, the signal-dependent afterpulsing background from a single photon avalanche diode was suppressed. This digital filter gate was characterized and optimized using photoluminescence decay lifetime measurements to show a reduction in systematic error that is 25% of the measured lifetime and ~500X improvement in acquisition time when compared with the time taken to obtain a comparably reliable result by reduction of the repetition rate to suppress afterpulsing. At 10 MHz, there is an increase in the linear dynamic range from ~2τ to ~6τ, where the lifetime, t, was measured to be (5.0±0.1)ns. Lifetime measurements were performed with a pulsed 510 nm diode laser, a 500 nm GaAs layer (sandwiched between InGaP capping layers), a silicon single-photon avalanche photodiode and time-correlated single photon counting electronics.