Constructor Institute’s breakthrough fuels quantum innovation
Constructor Institute’s breakthrough fuels quantum innovation

Schaffhausen, 26 October, 2023Constructor Institute is proud to announce a momentous breakthrough in quantum research: an innovative paper authored by Professor Wolfgang Tittel, Head of the Chair of Quantum Communications at Constructor Institute and distinguished figure affiliated with Constructor Institute in Schaffhausen, and his team, has been accepted for publication in the prestigious journal, Physical Review Letters. This milestone not only underlines Constructor Institute's prominence in quantum research but also confirms the strategic positioning of the entire Constructor ecosystem in quantum technologies through Constructor Knowledge, its education and research provider, and its funding arm Constructor Capital.

Leading the quantum revolution: Constructor Capital’s leading role

In 2022, the quantum sector attracted a record $2.35 billion in investments, signaling its transformative potential. In the words of Constructor Capital's management, “As the quantum market is projected to potentially unlock up to $1.3 trillion in value by 2035 across industries like automotive, chemicals, financial services, and life sciences, Constructor Capital’s portfolio companies —QuEra, Qnami, and Qruise— are not just participants but leaders at the forefront, shaping this quantum revolution”. The recent breakthrough with Er3+ ions highlights the group’s pivotal role in the development of advanced quantum networks, further emphasizing the strategic importance of the Swiss-Geneva base in driving global quantum innovation.

Strategic quantum collaboration in Geneva

Constructor Institute's Professor Tittel and his team have conducted pioneering research in a collaborative venture with students from the University of Geneva and Professor Simon Gröblacher’s group at TU Delft. They have harnessed cutting-edge facilities within the newly established Geneva laboratory, with a laser focus on tapping into the unique properties of individual Erbium ions as quantum network nodes, effectively addressing critical challenges in the field.

Professor Wolfgang Tittel, the lead author, stated, “This demonstration, three years in the making, is a big step for us. It lets us create single photons and, in the future, paired ones using the same materials we use for quantum memories. This compatibility is key for building functional quantum networks. We had to learn new technology, like making tiny optical resonators, and I'm grateful for the collaboration with Simon Gröblacher and his team.”

He added, “This research reflects the dedication and innovation of our Constructor Institute team. It advances quantum research and solidifies our presence and expertise in this rapidly evolving field.”

Erbium ions: catalysts for quantum advancements

Erbium (Er3+) ions, known for their 1.5 μm optical transition within the telecom band and extended spin coherence times, have long held promise as a foundation for quantum information processors and nodes. Notwithstanding persistent challenges, such as extended excited state lifetimes and inhomogeneous broadening of optical transitions, the joint team has surged ahead.

Aggressive pioneering quantum advancements

In their groundbreaking paper, the research team successfully demonstrates the linear Stark tuning of the emission frequency of a single Er3+ ion embedded in a lithium niobate crystal. The technique involves evanescently coupling these ions to a silicon nano-photonic crystal cavity, leading to a remarkable increase in the measured decay rate. By applying an electric field across the crystal, the team achieves Stark tuning that surpasses the ion's linewidth without altering the single-photon emission characteristics. This achievement paves the way for developing quantum networks rooted in rare-earth ion technology.

Revealing the power of quantum interference

Among the most thrilling aspects of this research is its ability to observe single photons from individual rare-earth ions. This fundamental step is also pivotal in the creation of entangled photon pairs. In addition, precise control of emitted photon frequencies through electric fields promises to eliminate natural frequency drifts, ensuring the creation of indistinguishable single photons and allowing, in turn, quantum interference in a quantum network.

To access the full paper, click here. For more information about this innovative research and Constructor Institute's contributions to quantum science, visit

About Constructor Institute

Located in Schaffhausen, Switzerland, Constructor Institute offers computer science and software engineering expertise at Master of Science, Ph.D., and postdoctoral levels. Our professors hold chairs in Quantum Software Engineering, Software Engineering, and Software Testing and Analysis Research. They are authors of multiple distinguished publications in their related fields.

With a commitment to building a sustainable future, Constructor Institute Schaffhausen prioritizes equal opportunities and gender equality, fostering an inclusive environment that empowers educators, staff, and students to thrive and contribute to innovation and the generation of knowledge.

With a focus on Computer Science and Quantum Technology, Constructor Institute strives for excellence in research, technology, innovation, education, and mentoring, leading the way in fundamental and applied research areas such as formal methods, quantum communications, software engineering for AI, and embedded systems.

About Constructor Group

Constructor Group is a global institution founded in 2019 by Dr. Serg Bell, a long-time tech and education entrepreneur and investor. Through its ecosystem, which includes a private university, research capacities, businesses, consulting services, and smart capital, Constructor Group aims to provide an innovative educational approach that covers the entire learning lifecycle and generate technology breakthroughs in five fundamental technology trends: machine intelligence, quantum technology, intelligent materials, hybrid reality, and life engineering.

The Constructor ecosystem consists of: 

  • Constructor Knowledge:a provider of education services, including traditional and online education programs and courses for people of all ages via its various affiliates. Constructor Knowledge provides advisory and strategic services to education institutions in the fields of student recruitment, communications, and marketing support. Its subsidiaries include Constructor Academy. The greater Constructor Knowledge ecosystem includes Constructor University in Bremen, Germany, and Constructor Institute in Schaffhausen, Switzerland.
  • Constructor: an all-in-one platform for education and research. With expertise in machine intelligence and data science, Constructor is built to cater to the needs of schools, higher education, corporate training, alternative credentials, and professional sports, offering solutions for teaching and administration, learning and research. From infrastructure to applications, Constructor elevates learning experiences, empowers educators, and drives research breakthroughs.
  • Constructor Capitala science-based global Venture Capital fund investing in early-stage startups in software and deep technology. The team members have extensive experience in startup and technology transfer, founded several large-scale global tech companies, including Acronis, Parallels, and Acumatica, and worked in leading consulting firms such as McKinsey & Company. The primary aim is to assist visionary founders in building groundbreaking companies across three vital sectors: Software, Deep Tech, and Edu Tech.

For more information and to explore the Constructor ecosystem, please visit

For media inquiries, please contact, Amandine Ambregni, Constructor Knowledge’s Director of Communications and Content at