Cat qubits exponentially suppress bit-flip errors, which means the error-correcting codes that protect them don’t have to be built like everyone else’s. Designing codes that exploit this noise bias is one of the most direct levers to shrink the hardware cost of a useful quantum computer, and it is exactly what this PhD is about.
Location & life at Alice & Bob:
As part of the QuBriC training programme, depending on the advancement of the project, you may have 3 secondments:
- Inria (France): fault-tolerant gate protocols and validation under realistic biased noise
- TU Delft (Netherlands): experimental benchmarking and integration of biased-noise gate demonstrations
- University of Navarra (Spain): modelling and simulation of bias-adapted code performance
Responsibilities:
- Develop and benchmark high-rate, biased-noise-adapted QEC codes and corresponding logical-gate protocols using lifted-product and asymmetric-distance constructions
- Co-design logical operations (homomorphic CNOT, transversal Clifford, algorithmic subroutines), incorporating noise bias, connectivity, and measurement constraints
- Validate designs via hardware-in-the-loop simulations and small-scale cat-qubit experiments, quantifying space–time efficiency and logical error suppression
- Benchmark biased-noise performance and decoder compatibility, providing feedback to the network’s architecture and decoder work packages
- Contribute to an open online library of high-rate codes and logical protocols for biased-noise qubits, including analysis of resource overhead, and to open datasets/tools for reproducible biased-noise co-design
- Publish your results in leading journals and present them at international conferences
- Follow the QuBriC doctoral training programme (QEC foundations, coding theory, architectures, decoders, hardware integration), Sorbonne Université doctoral training courses, plus Alice & Bob’s internal courses on biased noise, QEC, and cat qubit hardware
- Carry out the secondments and contribute to the network’s outreach and open-science activities
Requirements:
- MSc degree in Quantum Engineering or Physics completed by the recruitment date
- Demonstrated background in quantum information or quantum computing (coursework, thesis, or research projects visible on your CV)
- Proficiency in scientific programming with Python
- Proficiency in English (written and oral)
- MSCA eligibility - doctoral candidate: you must NOT already hold a doctoral degree hat the date of recruitment
- MSCA eligibility - mobility rule: you must not have resided or carried out your main activity (work, studies, etc.) in France for more than 12 months in the 36 months immediately before your recruitment date (short stays such as holidays and compulsory national service are not counted)
- Full-time availability for the 36-month appointment, including the secondments.
We’re also looking for:
- Familiarity with quantum error correction - stabilizer formalism, fault-tolerant logic
- Familiarity with the physics of cat qubits
- Experience with QEC simulation or resource-estimation tooling, and taste for open, reproducible science
- Prior research experience in a quantum computing company or lab (internship, research assistantship)
- Gross salary 1st year : 37 000 euros
- Gross salary 2nd year : 42 000 euros
- Gross salary 3rd year : 47 000 euros
Host institution / employer: Alice & Bob SAS, Paris (Île-de-France)
Doctoral enrollment: Sorbonne Université
Supervision: Dr Christophe Vuillot (Alice & Bob), with academic co-supervision under the network’s joint supervision agreements
Duration: 36 months, full-time
Expected start date: 01/12/2026