Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

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

David Alfonso Guzman

Published Jan 1, 2008• 0 citations
OpenAlex

Abstract

Basic in quantum communication and computing -- Quantum information -- Quantum communication -- Quantum protocols -- Experimental electronic requirements -- Photon detection -- Photon detection mechanisms -- Signal conversion and standardization -- The input circuit -- Information processor and applications : the FPGA -- Spartan-3 FPGA characteristics -- Other characteristics of ZestSC2 card -- Software used -- Built applications -- Outputs and control -- Electro-optic modulators -- Electric signal amplification -- The output circuit -- Results and analysis -- Input circuit -- Event frequency measurement -- Coincidence detection -- Time stamping -- Periodic signal generator -- Output circuit.

Related papers

High Performances Systems for Applications of Quantum Information

Andrea Stanco

This thesis work is about the realization of hardware and software systems for Quantum Random Number Generation (QRNG) and Quantum Key Distribution (QKD). Such systems were developed to guarantee a full functionality for a broader investigation of these two cutting edge applications of Quantum Information field. The thesis describes in details both the hardware and the software that were developed for FPGA-CPU board, Time-to-Digital converter (TDC) devices and computers, along with QRNG and QKD specific applications and their results. Randy was the first FPGA-based QRNG device to be developed; it uses a light source attenuated to single-photon level and one single-photon avalanche diode (SPAD). From the sampling of the SPAD electrical signal, the device produces random numbers through dedicated generation protocols and through the Peres unbiasing algorithm in order to maximize the output generation bit rate. Furthermore, the device allows to generate real time random numbers. This feature is used for the time setting of electro-optical components for extending Wheeler’s delayed-choice experiment to space. The same techniques were applied to a second device, LinoSPAD; it combines an FPGA-chip and a CMOS-SPADs array. Moreover, in this device, a TDC improves the photon detection time accuracy. Along with a dedicated post-processing based on Zhou-Bruk algorithm, the TDC allowed to reach a final bit rate equivalent to 300 Mbit/s. As far as QKD systems are concerned, within the collaboration among the University of Padova, the Italian Space Agency (ASI) with the Matera Laser Ranging Observatory (MLRO) and the Chinese Academy of Sciences (CAS) a TDC device management software was developed. The project aim is to realize a quantum cryptographic key exchange between the Chinese satellite Micius and MLRO. The software was designed to manage the entire data acquisition synchronized with UTC time. Furthermore, another software was designed to deal with electro-optomechanical and electro-optical components. The software is aim at the time-variant compensation of the beam angular changes through the optical path. Once again, within a collaboration between ASI and University of Padova, a full free space QKD system over tenths of kilometers was developed. It required the design of various components. This work describes the QKD source along with the dedicated FPGA board design. Such board generates the electrical impulses to control the qubit laser along with the electro-optic phase and intensity modulators.

•Nov 30, 2018•0 citations

Quantum computing with photons: introduction to the circuit model, the one-way quantum computer, and the fundamental principles of photonic experiments

Stefanie Barz

Abstract Quantum physics has revolutionized our understanding of information processing and enables computational speed-ups that are unattainable using classical computers. This tutorial reviews the fundamental tools of photonic quantum information processing. The basics of theoretical quantum computing are presented and the quantum circuit model as well as measurement-based models of quantum computing are introduced. Furthermore, it is shown how these concepts can be implemented experimentally using photonic qubits, where information is encoded in the photons’ polarization.

Journal of Physics B Atomic Molecular and Optical Physics•Mar 20, 2015•52 citations

Post-Measurement Adjustment of the Coincidence Window in Quantum Optics Experiments

Jaime Cariñe, Santiago Gómez, Giannini F. Obregon +4 more

We report on an electronic coincidence detection circuit for quantum photonic applications implemented on a field-programmable gate array (FPGA), which records each the time separation between detection events coming from single-photon detectors. We achieve a coincidence window as narrow as 500 ps with a series of optimizations on a readily-available and affordable FPGA development board. Our implementation allows real-time visualization of coincidence measurements for multiple coincidence window widths simultaneously. To demonstrate the advantage of our high-resolution visualization, we certified the generation of polarized entangled photons by collecting data from multiple coincidence windows with minimal accidental counts, obtaining a violation of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality by more than 338 standard deviations. Our results have shown the applicability of our electronic design in the field of quantum information.

IEEE Access•Jan 1, 2021•3 citations

Optical Quantum Information: Computing, Communication, and Metrology

Andrew G. White

Quantum information protocols range from subtle but straightforward — e.g., cryptography via quantum key distribution — to greatly complicated, notably quantum computation. To date, quantum cryptography has been realised in a variety of optical systems, whilst there is currently a worldwide effort to identify, implement and characterise suitable physical systems for quantum computation [1]. In this talk we look at optical systems for quantum computation, communication, and metrology.

Frontiers in Optics•Jan 1, 2005•0 citations

Feedback Circuit Module in Frequency-Nondegenerate Entanglement Swapping Experiment

Ziru Sang, Xiao Qiang Jiang, Tianming Zhao +2 more

In this paper, a dedicated feedback circuit module is designed for an experiment of entanglement swapping with frequency-nondegenerate photons. This experiment, aiming to entangle two frequency-nondegerate photons without prior interaction, is an advanced strategy for quantum communication. The key point of the experiment is to actively compensate a random phase shift originating from the frequency difference. The feedback circuit module has functions of measuring the time intervals, converting the time information to control level codes, and outputting control levels to an electro-optic modulator (EOM). A precision TDC is implemented in a field programmable gate array (FPGA) with 40 ps per LSB ( σRMS is less than 30 ps). A programmable look-up table is used as computing unit. The propagation delay time of the whole circuit module is less than 110 ns.

IEEE Transactions on Nuclear Science•Aug 22, 2013•2 citations

Quantum information processing: basic ideas, implementations, and possible impact on communications

Anders Karlsson

The tutorial will review the field of quantum information processing, i.e. quantum cryptography, quantum error correction codes, quantum computing..., starting from basic ideas, to the present state-of-the-art. We will also identify some critical technologies as well as discuss the potential impact on communications.

European Conference on Optical Communication•Jan 1, 1997•0 citations
Basic in quantum communication and computing -- Quantum information -- Quantum communication -- Quantum protocols -- Experimental electronic requirements -- Photon detection -- Photon detection mechanisms -- Signal conversion and standardization -- The input circuit -- Information processor and applications : the FPGA -- Spartan-3 FPGA characteristics -- Other characteristics of ZestSC2 card -- Software used -- Built applications -- Outputs and control -- Electro-optic modulators -- Electric signal amplification -- The output circuit -- Results and analysis -- Input circuit -- Event frequency measurement -- Coincidence detection -- Time stamping -- Periodic signal generator -- Output circuit.
This thesis work is about the realization of hardware and software systems for Quantum Random Number Generation (QRNG) and Quantum Key Distribution (QKD). Such systems were developed to guarantee a full functionality for a broader investigation of these two cutting edge applications of Quantum Information field. The thesis describes in details both the hardware and the software that were developed for FPGA-CPU board, Time-to-Digital converter (TDC) devices and computers, along with QRNG and QKD specific applications and their results. Randy was the first FPGA-based QRNG device to be developed; it uses a light source attenuated to single-photon level and one single-photon avalanche diode (SPAD). From the sampling of the SPAD electrical signal, the device produces random numbers through dedicated generation protocols and through the Peres unbiasing algorithm in order to maximize the output generation bit rate. Furthermore, the device allows to generate real time random numbers. This feature is used for the time setting of electro-optical components for extending Wheeler’s delayed-choice experiment to space. The same techniques were applied to a second device, LinoSPAD; it combines an FPGA-chip and a CMOS-SPADs array. Moreover, in this device, a TDC improves the photon detection time accuracy. Along with a dedicated post-processing based on Zhou-Bruk algorithm, the TDC allowed to reach a final bit rate equivalent to 300 Mbit/s. As far as QKD systems are concerned, within the collaboration among the University of Padova, the Italian Space Agency (ASI) with the Matera Laser Ranging Observatory (MLRO) and the Chinese Academy of Sciences (CAS) a TDC device management software was developed. The project aim is to realize a quantum cryptographic key exchange between the Chinese satellite Micius and MLRO. The software was designed to manage the entire data acquisition synchronized with UTC time. Furthermore, another software was designed to deal with electro-optomechanical and electro-optical components. The software is aim at the time-variant compensation of the beam angular changes through the optical path. Once again, within a collaboration between ASI and University of Padova, a full free space QKD system over tenths of kilometers was developed. It required the design of various components. This work describes the QKD source along with the dedicated FPGA board design. Such board generates the electrical impulses to control the qubit laser along with the electro-optic phase and intensity modulators.
Abstract Quantum physics has revolutionized our understanding of information processing and enables computational speed-ups that are unattainable using classical computers. This tutorial reviews the fundamental tools of photonic quantum information processing. The basics of theoretical quantum computing are presented and the quantum circuit model as well as measurement-based models of quantum computing are introduced. Furthermore, it is shown how these concepts can be implemented experimentally using photonic qubits, where information is encoded in the photons’ polarization.
We report on an electronic coincidence detection circuit for quantum photonic applications implemented on a field-programmable gate array (FPGA), which records each the time separation between detection events coming from single-photon detectors. We achieve a coincidence window as narrow as 500 ps with a series of optimizations on a readily-available and affordable FPGA development board. Our implementation allows real-time visualization of coincidence measurements for multiple coincidence window widths simultaneously. To demonstrate the advantage of our high-resolution visualization, we certified the generation of polarized entangled photons by collecting data from multiple coincidence windows with minimal accidental counts, obtaining a violation of the Clauser-Horne-Shimony-Holt (CHSH) Bell inequality by more than 338 standard deviations. Our results have shown the applicability of our electronic design in the field of quantum information.
In this paper, a dedicated feedback circuit module is designed for an experiment of entanglement swapping with frequency-nondegenerate photons. This experiment, aiming to entangle two frequency-nondegerate photons without prior interaction, is an advanced strategy for quantum communication. The key point of the experiment is to actively compensate a random phase shift originating from the frequency difference. The feedback circuit module has functions of measuring the time intervals, converting the time information to control level codes, and outputting control levels to an electro-optic modulator (EOM). A precision TDC is implemented in a field programmable gate array (FPGA) with 40 ps per LSB ( σRMS is less than 30 ps). A programmable look-up table is used as computing unit. The propagation delay time of the whole circuit module is less than 110 ns.