Four PhD Positions in Natural Language Processing, AI and LLM Security (CPH)

The Technical Faculty of IT and Design, Department of Computer Science, Section for Copenhagen, Natural Language Processing

The Department of Computer Science at The Technical Faculty of IT and Design invites applications for four fully funded PhD stipends in the area of Natural Language Processing (NLP), AI, and LLM Security. The positions are open for appointment from May 1, 2026 or soon thereafter - starting dates after the summer of 2026 are also possible. The duration of the positions are three years each. The positions are at AAU’s Copenhagen campus, located at the waterfront in Sydhavnen.

The positions are hosted within the Natural Language Processing (NLP) research group at AAU Copenhagen, and are supervised by Professor Johannes Bjerva. The NLP group is a rapidly expanding research environment with strong activities in multilingual NLP, LLM security, linguistically informed approaches to NLP, factuality in LLMs, and socially sustainable AI. The group is supported by several major national and international research grants and is currently scaling up its research capacity – in 2026, we are expanding with four postdocs who are expected to work closely with the ph.d. students hired in this call. As a PhD student, you will join a highly collaborative, international, and ambitious research community, with access to state-of-the-art computational resources. The positions feature the possibility of going on one or more longer stays abroad to facilitate knowledge exchange with top research environments worldwide. The positions are funded by a DFF: Sapere Aude project (“Building TRUST in Text: Linguistically Motivated Language Model Detection”) and an NNF: Ascending Data Science Investigator project (“LM2-SEC: Linguistically Motivated Language Model Security”).

Your work tasks

As a PhD student, you will conduct research at the intersection of Security, Safety, and Privacy in Natural Language Processing and AI, with a particular focus on Large Language Models (LLMs) and LLM-based systems.

Possible research directions include (but are not limited to):

• Detection and mitigation of backdoors, data poisoning, and adversarial inputs in LLMs
• Detection of LLM-generated text, in particular in situations where a model has been compromised but is generating bening outputs, e.g. via computational linguistic analysis of output space distributions
• Linguistically motivated methods for analysing and securing LLM behaviour, including, e.g., LLM misbehaviour and memorization in LLMs
• Analysis of vulnerabilities in low-resource language settings, and the effect of typological diversity on the security landscape in multilingual settings
• Formal semantic or symbolic methods for monitoring, evaluating, and improving LLM robustness.

The positions are embedded in an active and rapidly growing research environment, including ongoing projects on, e.g., AI security, linguistically motivated NLP, and knowledge-graph grounded factuality in LLM. The PhD students will work both independently and collaboratively within the group, and will have opportunities to engage with national and international partners. As a part of the projects funding these positions, we plan to host internationally leading researchers at AAU to provide further opportunities for knowledge exchange and collaboration.

Your competencies

We are looking for candidates motivated to make fundamental scientific contributions to NLP and AI security.

Applicants must have:

• A relevant MSc degree (e.g., Computer Science, Software Engineering, Machine Learning, Artificial Intelligence, Computational Linguistics, or a related field)
• Strong skills in machine learning and deep learning
• Experience with modern NLP methods, including transformer models
• Excellent communication skills in English

Applicants with prior experience in NLP, LLM architectures, security, privacy, safety, or robustness will be preferred.

Qualification requirements
PhD stipends are allocated to individuals who hold a Master's degree. PhD stipends are normally for a period of 3 years. It is a prerequisite for allocation of the stipend that the candidate will be enrolled as a PhD student at the Technical Doctoral School of IT and Design in accordance with the regulations of Ministerial Order No. 1124 of September 19, 2025 on the PhD Programme at the Universities and Certain Higher Artistic Educational Institutions. According to the Ministerial Order, the progress of the PhD student shall be assessed at regular points in time.

Who we are

According to the most recent US News and World Ranking, Aalborg University ranks 3rd in Europe and 27th in the world within Best Universities for Engineering. According to a 2018 MIT report, Aalborg University is considered to have the 4th best engineering program in the world. According to the recent Times Higher Education Impact ranking, Aalborg University ranks 9th in the World for UN SDG Impact.

The Department of Computer Science at Aalborg University is highly regarded among researchers, students, and external partners because of our leading research, education, and collaboration. The department currently has more than 170 scientific staff, 20 administrative staff, and 1,100 students, which are based on AAU's problem-based learning model. You can read more on www.cs.aau.dk, and you can read more about the TECH faculty here.

The Section for Copenhagen at the department is a rapidly growing and highly collaborative research environment, currently expanding from around 30 employees to approximately 60 over the next few years. The section includes members from research groups within NLP, AI, ML, Databases, Formal Methods, Human-Centred Computing, and others, and is uniquely characterised by an open, friendly, and supportive atmosphere. We place a strong emphasis on psychological safety, diversity, and inclusive research practices, and work actively to cultivate a positive everyday environment where staff and students can thrive. Daily life in the section is marked by informal interactions, knowledge sharing, and a strong sense of community. We also host a bi-weekly SemiBar (a combined seminar and Friday bar), where staff is challenged to present their research in a manner that provokes discussion across our diverse scientific backgrounds, along with regular social events, reading groups, cross-group research activities, and a newly established local PhD organization promoting an active social and scientific life among our most junior researchers. Together, these initiatives create a dynamic and welcoming environment for early-career researchers and senior staff alike.

The Natural Language Processing (NLP) group, led by Professor Johannes Bjerva, is a rapidly expanding research environment specialising in multilingual NLP, LLM security, linguistically informed AI, and trustworthy language technologies. The group hosts several major research projects funded by, e.g., the Carlsberg Foundation, Danmarks Frie Forskningsfond (DFF), the Novo Nordisk Foundation, and AAU’s AI:X initiative. During 2026, the group will grow to comprise 4 faculty, 4 postdocs, and 10 PhD students, in addition to several research assistants. The group collaborates broadly across Europe and globally, and offers an inclusive, ambitious, and supportive research culture.

How to apply
Your application must include the following:

• Application letter, stating your motivations for applying and your qualifications in relation to the position – at most one page.
• Curriculum Vitae (CV), at most two pages in addition to a list of any publications
• Diplomas (bachelor and master's degree diploma)
• Project description: Applicants are required to submit, along with their application documents, indicating their vision for research to be conducted in relation to the project topics outlined above – at most two pages.
• Other relevant documents

The application must be submitted via Aalborg University’s recruitment system, which can be accessed under the job advertisement on Aalborg University's website.

Aalborg University wants to reflect the surrounding society and has diversity as a core value. Therefore, everyone, regardless of personal background and orientation, is encouraged to apply for the position.

Do you have any questions?
If you have any questions about the position, you are more than welcome to contact us. You will find contact persons at the bottom of the jobpost.
Further information
We recommend that you save a copy of the job posting, as it will be removed once the application deadline has passed.

The assessment of candidates for the position will be carried out by qualified experts.
Shortlisting will be applied. This means that after the application deadline, the head of the department, with the assistance of the hiring committee, will select the applicants to be assessed. All applicants will be informed whether they have been shortlisted for assessment or not.

The hiring process at Aalborg University may include a risk assessment as a tool to identify potential risks associated with new hires, ensuring the safety, compliance, and integrity of the workplace.

Read more about The Technical Doctoral School of IT and Design

Salary and terms of employment
The employment is in accordance with the Ministerial Order on the Appointment of Academic Staff at Universities (the Appointment Order) and the Ministerial Order on Job Structure for Academic Staff at Universities (in Danish) and protocol on certain terms of employment of academic staff at universities (in Danish).

Salary and terms of employment are in accordance with the collective agreement between the Danish Confederation of Professional Associations and the state (AC collective agreement) (in Danish) and protocol on certain terms of employment of academic staff at universities (in Danish).