Doctoral Candidate/PhD Student for Ultra-low Latency Decoding of Quantum Codes

About this position

Introduction

Are you fascinated by quantum computers and eager to help make that potential a reality? Do you enjoy research and want to join a world-class European consortium shaping the future of quantum computing? Then join QuBriC, a pan-European doctoral network on quantum error correction, as a PhD candidate at Karlsruhe Institute of Technology (KIT) in Germany, designing next-generation codes and decoders for real quantum hardware.

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 cafe