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

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)

PIC Transmitter for QKD in the C-Band Integrated on a Commercially Available InP Platform

Borislav Hinkov, Delia Maria Fugger-Schafhauser, Florian Dubois, Florian Prawits, Martin Achleitner, Jasmin Spettel, Tommaso Cassese, A. Schönau, Moritz Kleinert, Hannes Hübel, Andreas Poppe

Published Jun 23, 2025• 0 citations
Publisher

Abstract

Quantum key distribution (QKD) will play a crucial role to keep the digital communication secure especially against the ‘store now, decrypt later’ attack, which could limit the lifetime of confidential data. Even current QKD systems built with discrete components [1] already reached high TRL levels and are broadly deployed in the field, the sovereignty of supply chains and future cost benefits calls for photonic integration to reach similar TRL levels.

DOI
10.1109/cleo/europe-eqec65582.2025.11109967

Related papers

Photonic Integrated Circuit for Compact Quantum Key Distribution

Martin Achleitner, Aaron Stadler, Marie-Christine Roehsner +5 more

For the establishment of secure communication as well as a future quantum internet, technologies like Quantum Key Distribution (QKD) must become smaller in size, cost-effective in production and more performant. Since attacks like store-now-decrypt-later are already a threat for sensitive data, research in this area must be pushed towards a higher practicality. In this work we show the feasibility of using a photonic integrated circuit (PIC) for application as a QKD transmitter. The PIC (provided by Eindhoven University of Technology) comprises a ring laser source, a Mach-Zehnder interferometer (MZI) with integrated RF phase modulators used for pulse carving and phase modulation as well as an attenuator section. This indium phosphide (InP) chip enables us to generate the necessary states for a 4-state time-bin-phase BB84 protocol [1] implementation. After characterization of all the photonic components and preliminary testing, we were able to generate a secret key rate of approximately 89kbps for 50MHz signal repetition rate with a QBER of 1.3% (in Z-Basis) in a back-to-back configuration.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•Jun 23, 2025•0 citations

Integrated QKD and QRNG Photonic Technologies

J. Aldama, Samael Sarmiento, Ignacio H. López Grande +3 more

Quantum key distribution (QKD) and quantum random number generation (QRNG) will play a key role in the future of data communication security. QKD can be used by trusted parties to share a secret key, leading to long-term secure communications. QRNG allows the production of fully unpredictable and certifiable random numbers, which can be used in numerous applications, including cryptography and large stochastic simulations. Both QKD and QRNG can be implemented using commercially available photonic components, which are mostly bulky and assembled into a discrete module. Although this approach can benefit from the superior performance and maturity of each individual component, it does not guarantee the large-scale deployment and commercial viability of the technology. A preferable alternative relies on integrating some or all functionalities in a single photonic integrated circuit (PIC) fabricated at the wafer scale, in this way reducing size, weight, complexity, cost, and power consumption. Integrated photonics can thus dramatically improve the performance and reliability of QKD systems and QRNG devices. Here, we review recent literature on designs, related materials, and fabrication processes, which is representative of state-of-the-art PIC-based QKD and QRNG. We conclude the paper by pointing out the challenges that need to be addressed in the future for reaching a wide-scale deployment of these integrated technologies.

Journal of Lightwave Technology•Nov 4, 2022•31 citations

Highly integrated quantum key distribution transmitter enabled by silicon photonics

Rende Liu, Yan-Lin Tang, Cheng-Guang Dong +7 more

Quantum key distribution (QKD) provides information-theoretic security independent of computational assumptions, yet the bulk and cost of current systems hinder large-scale deployment. Although integrated photonic technologies have enabled highly integrated QKD chips, practical QKD transmitters are still predominantly implemented as rack-mounted systems. Here, we demonstrate a highly integrated standalone QKD transmitter that integrates all essential functionalities required for practical QKD operation within a compact platform built around a silicon photonic encoding chip. The transmitter occupies only $167 \times 56 \times 21~\mathrm{mm}^3$ ($\sim 0.2~\mathrm{dm}^3$), comparable in size to a half-height, half-width PCIe card and more than 30 times smaller in volume than a conventional 1U rack-mounted system. Paired with a conventional discrete-component receiver, it achieves a secure key rate of 219.1 kbps over 51.3 km of standard single-mode fiber, with performance comparable to that of conventional discrete-component implementations. This work bridges the gap between photonic chip integration and deployable QKD hardware, marking an important step toward transitioning QKD transmitters from conventional rack-mounted equipment to compact board-level platforms.

quant-pharXiv:2607.23413•Journal of Lightwave Technology•Jul 28, 2026•0 citations

Towards On-Chip Continuous-Variable Quantum Key Distribution

Mélissa Ziebell, Mauro Persechino, Nicholas C. Harris +5 more

The distribution of secret keys with information-theoretic security, made possible by the laws of quantum mechanics, is undoubtedly one of the main achievements of quantum information processing and communications. In recent years, quantum key distribution (QKD) has been implemented in real-world conditions and commercial systems are now available. Despite this progress, however, QKD remains a relatively difficult to operate and costly technology, hindering its widespread use for high-security applications. The photonic integration of QKD devices can play a crucial role in this direction by reducing their size and cost by several orders of magnitude.

Conference on Lasers and Electro-Optics•Jun 21, 2015•15 citations

Integrated InP-based transmitter for continuous-variable quantum key distribution

J. Aldama, Samael Sarmiento, Luis Trigo Vidarte +9 more

Developing quantum key distribution (QKD) systems using monolithic photonic integrated circuits (PICs) can accelerate their adoption by a wide range of markets, thanks to the potential reduction in size, complexity of the overall system, power consumption, and production cost. In this work, we design, fabricate and characterize an InP-based PIC transmitter for continuous-variable (CV) QKD applications. In a proof-of-principle experiment implementing a pulsed Gaussian-modulated coherent state (GMCS) CV-QKD protocol over an optical fiber channel of 11 km, the system showed a performance compatible with a secret key rate of 78 kbps in the asymptotic regime. These results show the potential of InP technologies to integrate CV-QKD systems onto a monolithic platform.

arXiv:2412.03208•Optics Express•Feb 4, 2025•12 citations

Complete System Integration of Chip-Based Quantum Key Distribution Devices

Taofiq K. Paraïso, Thomas Roger, Davide G. Marangon +6 more

Solutions for a practical, wide-scale deployment of quantum secure communication devices have long been awaited for. Recent reports of quantum key distribution (QKD) chips, yet promising, were restricted to proof-of-concepts of individual components. We now demonstrate a complete QKD system, entirely based on photonic chips and distributing quantum secure encryption keys at high bit rate. This establishes photonic integration as a viable solution for a low-cost, scalable deployment of QKD.

Conference on Lasers and Electro-Optics•Jan 1, 2021•0 citations
Quantum key distribution (QKD) will play a crucial role to keep the digital communication secure especially against the ‘store now, decrypt later’ attack, which could limit the lifetime of confidential data. Even current QKD systems built with discrete components [1] already reached high TRL levels and are broadly deployed in the field, the sovereignty of supply chains and future cost benefits calls for photonic integration to reach similar TRL levels.
For the establishment of secure communication as well as a future quantum internet, technologies like Quantum Key Distribution (QKD) must become smaller in size, cost-effective in production and more performant. Since attacks like store-now-decrypt-later are already a threat for sensitive data, research in this area must be pushed towards a higher practicality. In this work we show the feasibility of using a photonic integrated circuit (PIC) for application as a QKD transmitter. The PIC (provided by Eindhoven University of Technology) comprises a ring laser source, a Mach-Zehnder interferometer (MZI) with integrated RF phase modulators used for pulse carving and phase modulation as well as an attenuator section. This indium phosphide (InP) chip enables us to generate the necessary states for a 4-state time-bin-phase BB84 protocol [1] implementation. After characterization of all the photonic components and preliminary testing, we were able to generate a secret key rate of approximately 89kbps for 50MHz signal repetition rate with a QBER of 1.3% (in Z-Basis) in a back-to-back configuration.
Quantum key distribution (QKD) and quantum random number generation (QRNG) will play a key role in the future of data communication security. QKD can be used by trusted parties to share a secret key, leading to long-term secure communications. QRNG allows the production of fully unpredictable and certifiable random numbers, which can be used in numerous applications, including cryptography and large stochastic simulations. Both QKD and QRNG can be implemented using commercially available photonic components, which are mostly bulky and assembled into a discrete module. Although this approach can benefit from the superior performance and maturity of each individual component, it does not guarantee the large-scale deployment and commercial viability of the technology. A preferable alternative relies on integrating some or all functionalities in a single photonic integrated circuit (PIC) fabricated at the wafer scale, in this way reducing size, weight, complexity, cost, and power consumption. Integrated photonics can thus dramatically improve the performance and reliability of QKD systems and QRNG devices. Here, we review recent literature on designs, related materials, and fabrication processes, which is representative of state-of-the-art PIC-based QKD and QRNG. We conclude the paper by pointing out the challenges that need to be addressed in the future for reaching a wide-scale deployment of these integrated technologies.
Quantum key distribution (QKD) provides information-theoretic security independent of computational assumptions, yet the bulk and cost of current systems hinder large-scale deployment. Although integrated photonic technologies have enabled highly integrated QKD chips, practical QKD transmitters are still predominantly implemented as rack-mounted systems. Here, we demonstrate a highly integrated standalone QKD transmitter that integrates all essential functionalities required for practical QKD operation within a compact platform built around a silicon photonic encoding chip. The transmitter occupies only 167×56×21 mm3167 \times 56 \times 21~\mathrm{mm}^3167×56×21 mm3 (∼0.2 dm3\sim 0.2~\mathrm{dm}^3∼0.2 dm3), comparable in size to a half-height, half-width PCIe card and more than 30 times smaller in volume than a conventional 1U rack-mounted system. Paired with a conventional discrete-component receiver, it achieves a secure key rate of 219.1 kbps over 51.3 km of standard single-mode fiber, with performance comparable to that of conventional discrete-component implementations. This work bridges the gap between photonic chip integration and deployable QKD hardware, marking an important step toward transitioning QKD transmitters from conventional rack-mounted equipment to compact board-level platforms.
The distribution of secret keys with information-theoretic security, made possible by the laws of quantum mechanics, is undoubtedly one of the main achievements of quantum information processing and communications. In recent years, quantum key distribution (QKD) has been implemented in real-world conditions and commercial systems are now available. Despite this progress, however, QKD remains a relatively difficult to operate and costly technology, hindering its widespread use for high-security applications. The photonic integration of QKD devices can play a crucial role in this direction by reducing their size and cost by several orders of magnitude.
Developing quantum key distribution (QKD) systems using monolithic photonic integrated circuits (PICs) can accelerate their adoption by a wide range of markets, thanks to the potential reduction in size, complexity of the overall system, power consumption, and production cost. In this work, we design, fabricate and characterize an InP-based PIC transmitter for continuous-variable (CV) QKD applications. In a proof-of-principle experiment implementing a pulsed Gaussian-modulated coherent state (GMCS) CV-QKD protocol over an optical fiber channel of 11 km, the system showed a performance compatible with a secret key rate of 78 kbps in the asymptotic regime. These results show the potential of InP technologies to integrate CV-QKD systems onto a monolithic platform.