Postdocs in Symmetry-Enhanced Quantum Cryptography - DTU Physics

Are you excited about information security and the novel possibilities opened by quantum technology? Are you fascinated by quantum physics and intriguing phenomena such as quantum entanglement, nonlocality, and indeterminism in quantum measurements? And are you keen to work in a fast-moving interdisciplinary field combining physics, math, and computer science?

At DTU Physics and DTU Compute we are seeking two postdoctoral candidates to work on theory of novel protocols, stronger security proofs, and efficient numerical techniques for semi-device-independent quantum cryptography. You will work within a synergetic, cross-departmental project in which we aim to leverage symmetries and representation theory to tackle scenarios with large systems and many parties that are intractable with existing methods.

The project is hosted within the Section for Quantum Physics and Information Technology (QPIT) at DTU Physics and the Cybersecurity Engineering Section at DTU Compute. The work will be carried out in close collaboration with colleagues in both host groups and benefit from the extensive combined expertise in fundamental and applied quantum physics, mathematics, and cryptography within the two sections.

You will be part of the teams lead by Prof. Jonatan Bohr Brask (DTU Physics) and Prof. Christian Majenz (DTU Compute).

QPIT is home to bigQ - Center for Macroscopic Quantum States - a Danish national Center of Excellence in quantum information science and technology. The purpose of the center is to explore quantum physics in new macroscopic regimes, deepening our understanding of quantum physics, and speeding up the development of emerging quantum technologies. Our main focus is basic research, but we strongly encourage and support innovation and industry partnerships. The center offers a stimulating and diverse working environment, comprising around 50 people (with 15 nationalities) including Faculty members, PhD students, postdocs, engineers and an administrator.

The Cybersecurity Engineering section at DTU Compute offers a vibrant and collaborative research environment in cybersecurity and cryptography. In cryptography, the research is focused on quantum-secure cryptography, foundational cryptographic theory, cryptographic protocols and symmetric-key cryptanalysis. The group maintains strong collaborations with leading institutions worldwide, creating an inspiring setting for high-impact research.

Responsibilities and qualifications 
We are looking for motivated candidates with strong theoretical skills and a solid background in relevant areas of research. You should be comfortable developing new ideas, taking initiative, and contributing actively to the direction of the project. We offer room for independent thinking as well as opportunities to collaborate across research groups, and we welcome applicants who are committed to producing impactful scientific results.

We expect you to:

• Be motivated and committed to conducting research at a high scientific standard.
• Enjoy working in a team, be willing to share your expertise with colleagues, and contribute with an open and collaborative mindset.
• Share our values of scientific curiosity and creativity.
• Be eager to take on complex challenges and find satisfaction in solving them.
• Appreciate and actively engage in constructive scientific discussions.

You should hold a PhD in physics, computer science, mathematics or a related field and have demonstrated strong theoretical skills relevant to the topic of the project.

Experience in any of the following areas is an advantage:

• Quantum cryptography (QKD, QRNG or other protocols)
• Representation theory
• Bell nonlocality and device independence
• Randomness extraction methods
• Semidefinite programming / convex optimisation for quantum information science
• Implementations of the Navascues-Pironio-Acín hierarchy

In addition, strong English communication skills, both written and spoken, are expected. 

You will contribute to the dissemination of the project’s results through scientific publications and presentations at international conferences and workshops.

You will also take part in supervising bachelor’s and master’s students - and potentially PhD students - while engaging actively in the academic life of the sections, including discussions, seminars, and community‑building events.

We offer
DTU is a leading technical university globally recognized for the excellence of its research, education, innovation and scientific advice. We offer a rewarding and challenging job in an international environment. We strive for academic excellence in an environment characterized by collegial respect and academic freedom tempered by responsibility. 

Salary and terms of employment 
The appointment will be based on the collective agreement with the Danish Confederation of Professional Associations. The allowance will be agreed upon with the relevant union. 

The period of employment is 2 years.

You can read more about career paths at DTU here.

Further information 
For more details about the job you may contact Associate Professor Jonatan Bohr Brask (jobb@dtu.dk) or Associate Professor Christian Majenz (chmaj@dtu.dk).

You can read more about DTU Physics at https://physics.dtu.dk/ and about DTU Compute at https://www.compute.dtu.dk/.

If you are applying from abroad, you may find useful information on working in Denmark and at DTU at DTU – Moving to Denmark.

Application procedure 
Your complete online application must be submitted no later than 2 March 2026 (23:59 Danish time). Applications must be submitted as one PDF file containing all materials to be given consideration. To apply, please open the link "Apply now", fill out the online application form, and attach all your materials in English in one PDF file. The file must include:

• Application (cover letter)
• CV
• Academic Diplomas (MSc/PhD – in English)
• List of publications 

Applications received after the deadline will not be considered.

All interested candidates irrespective of age, gender, disability, race, religion or ethnic background are encouraged to apply. As DTU works with research in critical technology, which is subject to special rules for security and export control, open-source background checks may be conducted on qualified candidates for the position.

Technology for people
DTU develops technology for people. With our international elite research and study programmes, we are helping to create a better world and to solve the global challenges formulated in the UN’s 17 Sustainable Development Goals. Hans Christian Ørsted founded DTU in 1829 with a clear mission to develop and create value using science and engineering to benefit society. That mission lives on today. DTU has 13,500 students and 6,000 employees. We work in an international atmosphere and have an inclusive, evolving, and informal working environment. DTU has campuses in all parts of Denmark and in Greenland, and we collaborate with the best universities around the world.