Monte Carlo calculation and measurement of shot-noise reduction factor

The frequency characteristic of the shot-noise reduction factor (R
²
) of the "
O
"-type diode is investigated by three methods: the first is a Monte Carlo calculation following the approach of Tien and Moshman and changing the pseudorandom numbers; the second is a computer simulation of the reduction of the modulated electrons at the potential minimum; and the third is the experimental measurement of shot-noise reduction using photoemission electrons produced by a mode-locked ruby laser. It is found by the Monte Carlo calculation that the original results of Tien and Moshman are not characteristic of the general situation, especially with regard to the peak at the plasma frequency of the potential minimum, and with regard to the dip commonly called the Tien dip. Calculations of the shot-noise reduction factor both by the Monte Carlo method and by the computer simulation approach show a rather smooth high-pass frequency characteristic. This result is verified by the photoemission experiments where the measurement accuracy has been enhanced through the use of mode locking.