Technically speaking when you turn a laser's power down far enough, you start adjusting the probability that the laser will emit a photon. Many pulses will gene

Technically speaking when you turn a laser's power down far enough, you start adjusting the probability that the laser will emit a photon. Many pulses will generate zero photons, some will generate one, and a few might generate two or more. The two or more case is the scary one where an attacker could siphon off a photon to measure.