Fraunhofer IPMS and the Max Planck Institute of Quantum Optics (MPQ) have achieved significant results in generating arbitrary light distributions, which are also relevant to atomic quantum computing. Spatial light modulators can be used to stimulate a large number of atoms in desired positions at the same time via laser beam. Localized in this way, they become switchable information carriers for quantum computers or for other applications in quantum metrology and quantum simulation, marking a major stride toward scalable quantum systems. Quantum computers based on charged or neutral atomic qubits offer a wide array of advantages over alternative technologies. They permit intrinsically high quality in the in-dividual qubits — the charge carriers in the computer system — and thus achieve excellent coherence times and gate quality. For neutral atoms to become qubits, they need to be manipulated with high-precision lasers in their quantum states. Strontium atoms are among those used to generate qubits in atomic quantum computers. These atoms are manipulated in the UV range, as important electronic transitions that can be used to excite their quantum states can only be achieved in the ultraviolet spectral range. The Max Planck Institute of Quantum Optics has been researching how to arrange and address neutral atoms for some time now. The hardware needed for spatial modulation of the UV rays that are required is still under development. Currently, there is a lack of scalable and sufficiently precise solutions that can be used to excite qubits individually. Researchers working on the project have now demonstrated that high-quality optical dot grids can be realized in the relevant UV wavelength range with spatial light modulators (SLMs) based on piston mirror arrays. Fraunhofer IPMS has special expertise in these kinds of arrays. In an experiment led by the Max Planck Institute of Quantum Optics, the strontium atoms used to generate qubits are laser-cooled and trapped in optical dot grids. The project joined the partners’ complementary expertise in a bid to advance into new realms of atomic quantum computing. To this end, Fraunhofer IPMS further developed a micro-mirror-based SLM that can be used to generate programmable and highly precise patterns in the nanometer range. The phase patterns generated can then be converted into any kind of laser beam schema using suitable optics. As part of the project, a relevant element was provided to the Max Planck Institute of Quantum Optics for testing. Its performance was demonstrated across all fields. Future work will be geared toward trapping the tiny atoms in the focal points of the laser beams and holding them in certain positions. Laser beams acting in this way are known as “optical tweezers.” The atoms’ internal quantum states are then manipulated using high-precision pulses to perform quantum logic operations for quantum calculations. Dr. Michael Wagner from Fraunhofer IPMS says of the successful project: “Our SLM systems enable light modulation up to the deep UV range. Micromirror technology offers a wide range of advantages over liquid crystal-based light modulators, such as UV compatibility, higher modulation speeds up to the megahertz range and polarization-independent work.” Alongside Fraunhofer IPMS demonstrating that SLMs are suitable for quantum optical experiments in the UV range and the Max Planck Institute successfully qualifying the technology for the experimental set-up, the project also focused on evaluating the accuracy of the phase modulation. Phase control in a range significantly below one one-hundredth of a wavelength was demonstrated, meeting the most stringent requirements that apply to the quality of optical tweezers. The next step on the way to the quantum system The use of micromirror-based SLMs for pattern generation and qubit control opens up a whole new dimension in relation to accuracy and scalability. The demonstrator devel-oped and the project results are key parameters for targeted further development of the SLM-technology for applications in the quantum field. Going forward, they may serve as a sound basis for realizing an apparatus for addressing the atoms. One of the next goals is to develop SLMs that enable parallel generation of several thousand focused laser beams in the ultraviolet spectral range. Increasing the system’s speed is another area of focus. The 1 kHz that has been achieved at present is merely a starting value for significantly faster future modulators. More information can be found on the Fraunhofer IPMS website.  

Fraunhofer IPMS has developed a new key management system (KMS) specifically designed for use in quantum-secure networks. The system enables the secure exchange of secret keys and ensures reliable, secure data distribution across large-scale network infrastructures. In view of the computing power of future quantum computers, traditional methods of key distribution, such as RSA and Diffie-Hellman, are under increasing pressure. To mitigate this risk and ensure secure digital communication, Fraunhofer IPMS’s KMS software employs quantum key distribution (QKD) technology, which is rooted in quantum principles. This enables individual point-to-point connections to be linked into a scalable and secure network, allowing cryptographic keys to be distributed symmetrically and in a controlled manner across multiple nodes and domains. As a result, an additional end-to-end security and communication layer is created for critical infrastructures. QKD not only enables secure key exchange, but also detects any eavesdropping attempts, ensuring that interference is immediately reported to the relevant parties. Integrating QKD into a cybersecurity strategy therefore provides the highest possible level of protection against emerging quantum threats. Special features of the Fraunhofer IPMS Key Management System (KMS) Fraunhofer IPMS is a reliable partner for companies that require quantum-secure communication. With its many years of expertise, innovative technologies and cutting-edge research in quantum key distribution (QKD), the institute helps companies to safely overcome the challenges of quantum computing and to build networks that will stand the test of time. “Our key management system is at the heart of complex QKD networks,” explains Dr Alexander Noack from Fraunhofer IPMS. “It coordinates key requests, generates physically secure keys, reliably distributes them, and manages their lifecycle.” Centralized control via a modern, container-based architecture enables transparent, flexible and efficient management of even large networks. Thanks to its high scalability, the platform can be used in research and demonstration environments, as well as in large, multi-node networks. Fraunhofer IPMS is setting an important milestone for secure communication in the future with its system, which complies with the ETSI-GS-QKD-014 standard. High-performance quantum random sources ensure the highest security standards, and a QKD-encrypted communication layer secures key exchange, even over public networks. Fraunhofer IPMS is currently developing an inter-domain interface via shared trusted nodes to enable the future networking of multiple QKD domains. This will enable seamless interoperability and network expansion. Possible applications and benefits The KMS developed by Fraunhofer IPMS extends quantum key distribution from simple point-to-point links to full network infrastructures. This enables a wide range of sectors to benefit, including telecommunications and metro networks, critical infrastructure such as energy, transport and healthcare, data centers and cloud providers, government and research networks, as well as Industry 4.0 environments. Companies and public authorities can thus secure multiple sites simultaneously, without the need to install dedicated point-to-point connections for each individual link. “We have already successfully demonstrated the performance of our system in the QuNET+MOBIXHAP project, which explored various scenarios ranging from simple laboratory networks to complex topologies. In addition, our inter-domain interface, currently under development, will enable secure communication across domain boundaries and provide investment security for ‘Q Day’,” explains Dr Noack. Further information on quantum communication technologies at Fraunhofer IPMS and the new communication management system can be found on the institute’s website.

Delft, 20 January 2026 — Universidad Politécnica de Madrid (also referred to as UPM), through the Quantum Information and Computing Research Group, in collaboration with Q*Bird, has deployed Spain’s first Measurement-Device-Independent Quantum Key Distribution (MDI-QKD) network, connecting 3 end nodes, marking a significant milestone in Europe’s quantum communication infrastructure. The system is deployed in high-security operational environments, with installations spanning two sites of the Instituto Nacional de Técnica Aeroespacial (INTA) and one site of the Ministerio del Interior, Secretaría General de Sistemas de Información y Comunicaciones para la Seguridad (SGSICS), all located in Madrid. This development is part of UPM’s ongoing efforts to enhance the security and scalability of quantum communication networks through excellent research and development. The network follows a hub-and-spoke topology, consisting of Q*Bird’s Falqon® Series’ three end nodes, one center hub and a quantum optical switch, with fiber distances ranging between 30 and 50 kilometers from the center hub to each of the user end nodes. This architecture enables multi-node quantum key distribution (QKD) in a fully connected mesh network, without trusted nodes, even at the central hub, offering high scalability, making it suitable for metropolitan-scale deployments. Why MDI-QKD? Classical cryptography relies on computational complexity for security, leaving sensitive data fundamentally vulnerable to future quantum attacks. Even traditional QKD systems, while inherently quantum-secure, are limited by vulnerabilities at the measurement stage as detectors can be exploited by advanced attacks, potentially compromising key and system integrity. MDI overcomes this limitation by ensuring that all detectors exist at the center hub, which does not handle keys or other secrets at any point, and never has access to any keys, enabling highly secure, scalable multi-node networks. “A multi-node MDI-QKD network enables our researchers to evaluate key performance metrics and optimise network configurations for high-security scalable deployments,” said Laura Ortiz, Researcher at UPM. “Having the center hub on UPM premises facilitates maintenance and experimentation while reducing costs, but it also allows us to provide cryptographic services to third parties within the high-security ecosystem with effective trust management.” The technology behind the network At the core of the live network deployment is Q*Bird’s Falqon® Series: The MQX4000 center hub serves as the quantum connecting station, establishing quantum links between multiple nodes. The MQS4000 optical switch manages the optical transport layer, enabling dynamic distribution of QKD keys across the network. The MQT4000 user nodes act as quantum information transmitters, providing interfaces to secure cryptography key from the QKD protocol. This combination allows researchers at UPM to study key generation rates, latency, loss tolerance and interoperability under realistic metropolitan fiber conditions, creating a valuable platform for advancing future quantum communication standards. “The MadQCI ecosystem is more than a quantum network. It is a hub that attracts stakeholders seeking performance, interoperability and scalability solutions that are critical for a Europe-wide quantum infrastructure. Q*Bird’s MDI-QKD system is ideal for powering this all.” said Alberto Sebastián-Lombraña, Researcher at UPM. Building a quantum-resilient future The UPM deployment demonstrates that operational MDI-QKD networks are technically feasible, resilient and scalable. The network provides secure multi-node cryptographic quantum key distribution, supporting the development of advanced quantum key management systems and federated quantum network architectures. “By combining Q*Bird’s MDI-QKD Falqon® Series with UPM’s infrastructure, we are addressing the immediate threats posed by quantum computing while establishing a secure, scalable platform for future digital connectivity,” shares Dr. Joshua Slater, CTO of Q*Bird. “Trust and security are at the core of this deployment and every node, every link is designed to ensure that the quantum cryptographic keys exchanged cannot be compromised, even by the measurement devices themselves. This is a critical step toward building networks that customers can genuinely rely on.” Spain at the European quantum frontier UPM’s deployment of Q*Bird’s MDI-QKD Falqon® Series signals Madrid and Spain’s growing role as a hub for quantum innovation in Southern Europe, with potential economic and technological benefits. It is not just a research achievement, it is a foundation for a quantum-secure digital society. Q*Bird’s MDI-QKD Falqon® Series seamlessly integrates with UPM’s existing quantum infrastructure, including their ongoing Madrid Quantum Communication Infrastructure (MadQCI) initiative. As Spain’s first operational MDI-QKD network, this deployment lays the groundwork for interoperable quantum communication systems and contributes directly to the EuroQCI initiative, reinforcing Europe’s broader push toward a federated quantum internet. “By deploying yet another fully operational, multi-node MDI-QKD network, we are demonstrating that secure, scalable quantum communications are achievable today. We are thrilled to undertake this deployment in close partnership with UPM, who have been pioneers in QKD deployments and leaders in addressing the real-world challenges of integrating quantum security into existing network infrastructure. Working side by side with UPM on these complex challenges is an exciting milestone, and it reinforces the progress we are making toward building interoperable, industrial-grade quantum networks,” added Dr. Joshua Slater. “This is a benchmark for future continental networks and a tangible step toward a quantum-secure Europe.” “With this network, Spain is not just participating in Europe’s quantum future, it is helping define it,” added Vicente Martín, Principal Investigator of the Quantum Information and Computing Research Group. “We are creating a trusted foundation for secure, multi-node quantum networks that will underpin Europe’s digital sovereignty and research community. This assures and guarantees that the data moving through these trusted networks is truly secure.” UPM and Q*Bird’s collaboration strengthens Spain’s role in developing scalable, operational quantum networks, positioning the country as a key player in Europe’s quantum communications leadership. And this collaboration between UPM and Q*Bird sets a precedent for future initiatives aimed at integrating quantum technologies into critical communication networks. As the field progresses, such partnerships will be instrumental in building resilient systems capable of safeguarding sensitive information in the quantum era! About Universidad Politécnica de Madrid Quantum Information and Computing Research Group, led by Vicente Martín, researchs on the characterisation and integration of QKD systems in quantum networks; deployment of real quantum-communication infrastructures (notably, the team have deployed the largest QKD network in Europe to date); programmable quantum network control (software-defined networking for QKD); integration with classical cryptographic services (e.g., TLS, VPN, IPSec); modelling of current and future-proof quantum-communication networks; and new services and protocols beyond QKD (e.g., quantum-entanglement distribution networks, multiparty quantum secret sharing, entropy distribution, etc.). The team also focuses on knowledge transfer, including proof-of-concept demonstrations with industry, standardisation and entrepreneurship training. Website/contact: https://es.linkedin.com/company/giicc gi.icc@upm.es About Q*Bird Q*Bird is a leader in quantum-secure communication, based in Delft, The Netherlands. We provide cutting-edge solutions and expert support to ensure your data security. Our unique technology enables ultra-secure communication networks for critical infrastructure and commercial use. Q*Bird’s network technology uses the laws of quantum physics to provide proven secure cryptography keys that are immune to interception, ensuring your data remains safe from eavesdropping. Our Falqon® Series delivers a next-generation solution for Measurement Device Independent Quantum Key Distribution (MDI-QKD), offering unequalled security, scalability and flexibility without relying on trusted nodes, ensuring your data stays protected in transit, now and into the quantum future. As we secure today’s networks against quantum threats, we are building toward the future, developing technologies that will enable the quantum internet, including connectivity solutions for quantum processors, modems and sensors. This ensures organisations are prepared for the advent of the quantum internet and ready to harness its full potential. Join us at the forefront of quantum innovation and learn how the Falqon® Series can protect your organisation from data breaches and future-proof your network security against quantum threats! For more information, visit www.q-bird.com, contact info@q-bird.com, or follow Q*Bird on LinkedIn. Media Relations Contact: Name: Milu Sini Lal, Msc E-Mail: milu@q-bird.com Title: Marketing & Communication Specialist