Control systems for experiments in quantum communication and computing on optical fibres.

摘要

An electronic system enabling certain classes of quantum information processing experiments is designed and assembled. Requirements for the development of this system were obtained by studying particular quantum optical experiments, such as the implementation of coin tossing protocols, and cluster state generation.;The processing takes part in a field-programmable gate array, which has a USB communication channel for connection to any computer. External input/output ports serve to link the processing unit and peripheral devices. Outputs from different kinds of photon detectors and similar devices are processed by a custom designed printed circuit. Electro-optic modulators require signals that change their voltage levels during a single experience; a second printed circuit was designed to deal with this situation.;Graphical user interfaces are possible with the current system; some of them were done. Generation of all libraries that contains C code instructions suffices to program the card, send and receive both instructions and data during an execution of the loaded program.;This project provides a flexible, reprogrammable electronic system. It addresses required utilities such as single and coincident photon detection, time stamping of events, random number generation, and optical phase and amplitude control.