Are you up for the challenge of joining a highly ambitious research group involved in a joint project with international academic and industrial partners towards developing scalable technologies for quantum photonic networks? We are now strengthening our research team on quantum light sources in silicon and are opening three PhD positions within fabrication, characterization, and theory.

The overarching goal of this newly funded project is to realize quantum light sources coupled to quantum memories. Quantum memories are key components of optical quantum computers and scalable quantum networks: They are responsible for the central tasks of storing and processing quantum information. The memories must be optically active so distant nodes in a network can be entangled via single photons emitted by the memories. Erbium in silicon is currently subject to intense worldwide research [Berkman2023, Gritsch2025] because erbium is the only emitter that combines compatibility with semiconductors with long spin coherence time and emission in the low-loss telecom C-band.

We are looking for up to three PhD students, who have excelled in their studies, to join our team working towards demonstrating chip-scale quantum light sources with embedded quantum memories based on erbium in ultracompact tunable silicon nanocavities. You will be part of a well-funded project that builds on our recent experimental breakthroughs in ultra-small silicon nanocavities [Babar2023, Rosiek2023] with extreme light-matter interactions. We aim to combine fundamental theory, device design, and our unrivalled capabilities in high-resolution silicon nanotechnology towards entering so far uncharted experimental regimes.

Responsibilities and qualifications
The candidates will work closely together with each other and the rest of the Photonic Nanotechnology group at DTU Electro, as well as with commercial Danish and international academic collaborators on EQUAL – Erbium-based silicon quantum light sources, a newly initiated project funded by the Innovation Fund Denmark. We emphasize strong interaction between experiment and theory, independent thinking, and team spirit. The available projects are:

• Nanoelectromechanically tunable cavities with embedded erbium quantum light sources (mainly nanofabrication and characterization). A significant part of this work involves work in DTU’s state-of-the-art cleanroom, DTU Nanolab. Hands-on experience in nanofabrication combined will be an advantage.
• Nanoelectromechanically controlled photonic meshes for quantum and classical photonic information processing (mainly theory and characterization). Experience with theory of photonic information processing will be an advantage.
• Spectroscopy on silicon quantum light sources (mainly characterization and theory). Experience with experimental and/or theoretical quantum optics will be an advantage.

You must have a two-year master's degree (120 ECTS points) or a similar degree with an academic level equivalent to a two-year master's degree.

The details, responsibilities, and tasks of the PhD projects will be tailored to the qualifications and interests of the applicants but will revolve around the headlines above. Most importantly, we seek highly motivated and excellent students with an interest in teamwork and research at the highest international level.

Applicable for all scholarships

Approval and Enrolment  
The scholarships for the PhD degree are subject to academic approval, and the candidates will be enrolled in one of the general degree programmes at DTU. For information about our enrolment requirements and the general planning of the PhD study programme, please see DTU's rules for the PhD education .

Assessment
The assessment committee consists of Professor Søren Stobbe, email: ssto@dtu.dk  and Senior Researcher Mikkel Heuck, email: mheu@dtu.dk .

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 appointment terms
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 3 years. The starting date is 1 September 2025 or as soon as possible thereafter.

You can read more about career paths at DTU here http://www.dtu.dk/english/about/job-and-career/working-at-dtu/career-paths.

Further information
Further information may be obtained contacting Senior Researcher Mikkel Heuck or Professor Søren Stobbe.

You can read more about DTU Electro at www.electro.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 . Furthermore, you have the option of joining our monthly free seminar “PhD relocation to Denmark and startup “Zoom” seminar ” for all questions regarding the practical matters of moving to Denmark and working as a PhD at DTU.

Application procedure 
Your complete online application must be submitted no later than 9 July 2025 (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:

• A letter motivating the application (cover letter)
• Curriculum vitae 
• Grade transcripts and BSc/MSc diploma (in English) including official description of grading scale

In the field “Please indicate which position(s) you would like to apply for”, please indicate which project you are applying for (title from the above list of PhD projects  or individual research projects).

Incomplete applications will not be considered. You may apply prior to ob­tai­ning your master's degree but cannot begin before having received it. 

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

[Babar2023] Babar, A. N., Weis, T. A. S., Tsoukalas, K., Kadkhodazadeh, S., Arregui, G., Vosoughi Lahijani, B. & Stobbe, S. Self-assembled photonic cavities with atomic-scale confinement . Nature 624 , 57–63 (2023).
[Berkman2023] Berkman, I. R., Lyasota, A., de Boo, G. G., Bartholomew, J. G., Lim, S. Q., Johnson, B. C., McCallum, J. C., Xu, B.-B., Xie, S., Abrosimov, N. V., Pohl, H.-J., Ahlefeldt, R. L., Sellars, M. J., Yin, C. & Rogge, S. Millisecond electron spin coherence time for erbium ions in silicon . arXiv:2307.10021 (2023).
[Gritsch2025] Gritsch, A., Ulanowski, A., Pforr, J. & Reiserer, A. Optical single-shot readout of spin qubits in silicon . Nature Communications. 16 , 64 (2025).
[Rosiek2023]  Rosiek, C. A., Arregui, G., Vladimirova, A., Albrechtsen, M., Vosoughi Lahijani, B., Christiansen, R. E. & Stobbe, S. Observation of strong backscattering in valley-Hall photonic topological interface modes . Nature Photonics 17 , 386–392 (2023).

About the Quantum and Nanophotonics section at DTU Electro
The Department of Electrical and Photonics Engineering has nearly 300 employees of which around 200 research different aspects of photonics. Research is performed within nanophotonics, photonic nanotechnology, lasers, quantum photonics, optical sensors, LEDs, photovoltaics, ultra-high speed optical transmission systems, and bio-photonics. The Quantum and Nanophotonics section combines expertise in the synthesis and handling of nanomaterials, the fabrication of nanoscale devices, and theoreticians employing a wide palette of analytical and numerical techniques to provide better understanding of and control over the fundamental properties of light-matter interactions and in this way realizing new nanophotonic devices for emerging information and quantum technology.

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.