Relaxed and triggered photon counting distributions for laser and pseudo-thermal sources

P. R. Pearl, GORDON J. TROUP

Vladimir S. Starovoitov, Viacheslav N. Chizhevsky, D. B. Horoshko +1 more

Salim Ali Al-Kathiri, Wajdi Fawzi Mohammed Al-Khateeb, Mohd Hafizulfika +2 more

Key distribution system using faint laser is very likely to become the first application exploiting the particular properties of single quanta called photons. In experimental key distribution system, it is highly demanded to use single-photon source for secure key distribution. Since there is not yet a laser source capable of producing such faint state, most experiments uses low coherent pulse laser, which is attenuated to produce a mean photon number mu. In this paper, we present an experimental setup to determine the mean photon number using a 300-ps low coherent pulse laser at 1550 nm for a practical crypto system. We will also present the effect of trigger frequency, detection efficiency and dark counts on average photon counts.

Archibald W. Smith, John A. Armstrong

Anders Smith, J. Armstrong

M. L. Martínez Ricci, Javier Mazzaferri, A. V. Bragas +1 more

We present a photon counting experiment designed for an undergraduate physics laboratory. The statistics of the number of photons of a pseudo-thermal light source is studied in two limiting cases: much longer and much shorter than the coherence time, giving Poisson and Bose-Einstein distributions, respectively. The experiment can be done in a reasonable time using a digital oscilloscope without the need of counting boards. The use of the oscilloscope has the advantage of allowing the storage of the data for further processing. The stochastic nature of the detection phenomena adds additional value because students are forced to do data processing and analysis.