Counting photoelectrons in the response of a photomultiplier tube to single picosecond light pulses

We demonstrate the capability of a commercial photomultiplier to produce distinguishable anodic-pulse charge values when 1, 2, or more photoelectrons leave the cathode within a time shorter than the pulse-response duration. We propose a method for precise reconstruction of the photoelectron statistics from the measured pulse-height spectra and discuss applications to the characterization of quantum states in the continuous-variable regime.