Doctoral candidate / Research associate (f/m/d)

Job Description

The Communications Engineering Lab (CEL) at KIT is currently seeking to recruit, starting February 1st, 2027 or later, limited to three years, one

Doctoral candidate / Research associate (f/m/d)

working on the development of ultra-low latency parallelised decoding of quantum error correction coding schemes for future quantum computers within the framework of the European Doctoral Training Network “QuBriC” on “Bridging Quantum and Classical Error Correction for Scalable Fault-Tolerant Quantum Computing” (QuBriC Doctoral Candidate 3.3).

Your research will sit at the interface between the classical and quantum worlds. The position is part of QuBriC (https://www.qubric.eu/index.html), the first pan-European doctoral network dedicated entirely to quantum error correction, bringing together 16 academic institutions and 7 industrial partners across 11 countries. You will join a cohort of 15 doctoral candidates based in Europe's leading quantum error correction (QEC) groups, and you will meet them regularly at network-wide training schools, workshops and conferences.

You will be supervised by Prof. Dr. Laurent Schmalen (https://www.cel.kit.edu/english/team_schmalen.php) and Dr. Hedongliang Liu (https://www.cel.kit.edu/team_liu.php) at KIT.

You will carry out two secondments, one at University College London and one at Alice&Bob.

Research Programm Description

Quantum computers have grown remarkably fast. Qubit counts have risen year after year, driven by advances in fabrication, control electronics and system integration. Quality, however, has not kept pace. Today's qubits remain noisy, short-lived and vulnerable to crosstalk and correlated errors. Quantum error correction (QEC) is what turns this fragile hardware into something useful: it protects quantum information by encoding many noisy physical qubits into fewer, far more reliable logical ones. Without effective QEC, adding qubits does not add computing power, because errors accumulate faster than machines can scale. Despite impressive hardware progress, today's codes and decoders remain far too costly and too slow to make large-scale fault-tolerant quantum computing practical. Closing that gap is one of the defining challenges of the coming decade, and it is exactly where this PhD sits.

In this project, you will work on the design of ultra-low latency decoding algorithms for quantum error correcting codes to enable quantum computers. Rapid error correction is only of the biggest challenges in quantum computing and must be done continuously to ensure operation. The project allows various research directions:

• Extend BP and neural decoders to an ensemble-decoding framework for advanced qLDPC codes (e.g. Gross, Triavariate Tricycle codes), targeting low latency, scalability, and hardware integration.
• Develop new ensemble decoding schemes based on mathematical properties of the employed codes.
• Design codes towards constructions enabling low-latency decoders.
• Benchmark ensemble decoders against state-of-the-art methods (Relay-BP, single-shot) and assess feasibility under cat-qubit hardware constraints.

The exact direction of the project can be shaped according to your background and research interests. We are particularly interested in fundamental ideas that can ultimately lead to practical algorithms.

Your will conduct high-quality research within the project and progressively develop your own research ideas. You will develop algorithms and software, perform numerical experiments and theoretical analysis, and communicate your results through publications and presentations at leading international conferences and journals.

You will collaborate extensively with researchers within QuBriC and participate in the network's research, training, and dissemination activities.

Conditions of Employment

• The successful candidates will receive a gross salary of €3924,86, in accordance with the Marie Skłodowska-Curie Actions (MSCA) regulations for Doctoral Candidate researchers (the mobility allowance is included in the previous value). According to the MSCA regulation, if the recruited doctoral candidate has or acquires family obligations during the action duration, a family allowance of €407,47 will be added to the previous value, in case of eligibility. The salary values may change slightly due to individual health insurance contributions. The calculation is based on a health insurance employer share rate of 8.645%. Payment is according to the § 611 ff. BGB (Bürgerliches Gesetzbuch).
• The period of employment is 36 months. In addition to their individual scientific projects, all fellows will benefit from further continuing education, which includes secondments at both academic and industrial sectors, a variety of training modules including transferable skills courses and active participation in conferences.
• The Doctoral Candidates are expected to travel to network partners under two secondments for a typical duration of 3-6 months. Additionally, the Doctoral Candidates are expected to participate in outreach activities including, but not limited to, YouTube videos, social media updates, participation in public events and campaigns, as well as dissemination to popular press.
• We offer an attractive and modern working environment with access to excellent facilities of KIT, diverse and responsible tasks, a wide scope of advanced training options offered, e.g., by the Karlsruhe House of Young Scientists (KHYS), flexible working time models, a job ticket (BW) allowance, and a cafeteria/canteen.
• We prefer to balance the number of employees (f/m/d). Therefore, we encourage female applicants to apply for this job.
• If qualified, severely disabled persons will be preferred.

Application Procedure

We invite you to submit a complete application by via email to qubric@cel.kit.edu. The application should include a:

• Complete CV including a list of publications and contact information of two references. Kindly note that we may reach out to references at any stage of the recruitment process. We recommend notifying your references upon submitting your application. If more than one position is pursued in the QuBriC programme, please clearly indicate all the positions that are pursued with priorities on the first page of the CV.
• Motivation letter (maximum 1 page per position applied) should state why the applicant wishes to pursue the specific research and why the applicant thinks to be an ideal candidate for the position.
• Full academic transcripts and degree certificates for your Master's and Bachelor's programme, other courses followed, with grades and if possible, a ranking.
• Up to two written scientific reports in English (e.g. MSc thesis, traineeship report or scientific paper).
• A brief eligibility statement indicating your country/countries of main activity (work, studies, etc.) and residence over the last 3 years, with exact dates, to verify MSCA mobility eligibility.

Ensure that you submit all the requested application documents. We give priority to complete applications. Please note that all submitted applications will be checked against the defined eligibility and mobility criteria. Applications that do not follow these criteria will not be considered.

We look forward to receiving your application and will screen it as soon as possible. The vacancy will remain open until the position is filled.

We welcome your application no later than December 15, 2026.

Requirements

Skills/Qualifications

• A master's degree (or an equivalent university degree) in Electrical Engineering, Physics, Computer Science, Applied Mathematics, or a related field.
• A strong mathematical background, with roots in either communications engineering, information theory or quantum information science.
• Familiarity with classical and/or quantum coding theory, error correcting codes, decoding algorithms, or high-performance computing systems is considered a strong plus.
• Affinity with mathematical/statistical modelling and programming (e.g. Python, C/C++, MATLAB, or similar).
• A research-oriented attitude and strong motivation to deliver ambitious, high-quality work.
• Ability to work in an interdisciplinary team and interested in collaborating with industrial partners.
• A good command of spoken and written English (B2+ level), and the motivation to further develop your scientific communication skills during your PhD.

Specific Requirements

MSCA-DN Eligibility Rules

• The candidate cannot already be in possession of a doctoral degree at the date of recruitment.
• The candidate must not have resided or carried out their main activity (work, studies, etc.) in Germany for more than 12 months in the 36 months immediately before their recruitment date.