48-channel coincidence counting system for multiphoton experiment

In this paper, we demonstrate a coincidence countingsystem with 48 input channels which is aimed to count all coincidence events, up to 531  441 kinds, in a multiphotonexperiment. Using the dynamic delay adjusting inside the Field Programmable Gate Array, the alignment ofphoton signals of 48 channels is achieved. After the alignment,clock phase shifting is used to sample signal pulses. Logic constraints are used to stabilize the pulse width. The coincidence counting data stored in a 1G bit external random access memory will be sent to thecomputer to analyze the amount of 2-, 3-, 4-, 5-, and 6-fold coincidence events. Thissystem is designed for multiphoton entanglementexperiments with multiple degrees of freedom ofphotons.

Source: Review of Scientific Instruments - November 15, 2016 Category: Physics Authors: Chen Zhang, Wei Li, Yi Hu, Tao Yang, Ge Jin and Xiao Jiang Source Type: research