Alice & Bob is developing the first universal, fault-tolerant quantum computer to solve the world’s hardest problems.
The quantum computer we envision building is based on a new kind of superconducting qubit: the Schrödinger cat qubit 🐈⬛. In comparison to other superconducting platforms, cat qubits have the astonishing ability to implement quantum error correction autonomously!
We're a diverse team of 250+ brilliant minds from over 35 countries united by a single goal: to revolutionise computing with a practical fault-tolerant quantum machine. Are you ready to take on unprecedented challenges and contribute to revolutionising technology? Join us, and let's shape the future of quantum computing together!
Purpose of the role
In a context where magnetic flux noise directly limits the coherence of superconducting quantum circuits, Alice & Bob uses flux-tunable resonator chips as local probes of the electromagnetic environment seen by its quantum processors. The current measurement relies on a Pound-Drever-Hall (PDH) lock whose feedback loop bandwidth restricts the sensing to a narrow frequency band.
The Experimental Physics Intern, Broadband Flux Noise Sensing contributes to extending this capability to a broad frequency band by setting up and operating a cryogenic experiment to characterise these chips, identifying the limitations to broadband operation, and proposing and testing ways to overcome them.
Reporting to the Team Lead, HERMES, they will work closely with the quantum and RF characterisation engineers of the HERMES team to deliver a validated broadband flux noise sensing method.
The internship starts between January and March 2027 and lasts 6 months!
Responsibilities:
- Develop and set up the flux noise measurement experiment
- Design and assemble the cryogenic and RF measurement chain (wiring, filtering, amplification, instrumentation)
- Implement and document the measurement and control software in Python
- Characterise flux noise measurement chips
- Calibrate the flux-tunable resonators (frequency vs. flux, operating point, PDH lock parameters)
- Measure the flux noise power spectral density and extract the relevant metrics
- Analyse the limitations to broadband operation
- Model and measure the feedback loop bandwidth, latencies and noise contributions of the readout chain
- Identify the dominant physical and instrumental limits across the frequency band
- Propose and test solutions to extend the measurement bandwidth
- Evaluate alternative locking, readout or analysis schemes
- Implement and validate the most promising approaches experimentally
- Report and share results
- Document experiments, analyses and conclusions in the team's internal tools
- Present progress and findings to the HERMES team
Requirements:
You are a Master's student in physics, engineering physics or electrical/electronics engineering, with a strong interest in experimental work.
You combine a good theoretical grasp of electromagnetism and microwave systems with practical programming skills, and are comfortable building, operating and troubleshooting a measurement setup.
- LANGUAGES: Proficient in English
- EXPERIENCE: Prior lab or project experience in RF/microwave measurements or low-temperature physics; experience with cryostats or superconducting quantum circuits is a plus
- Solid understanding of magnetic fields, flux and electromagnetic coupling
- Knowledge of microwave engineering: waveguides, resonators, transmission lines, S-parameters
- Proficiency in Python for instrument control, data acquisition and analysis
- Understanding of feedback and control loops (gain, bandwidth, latency, stability)
- Familiarity with noise characterisation and spectral analysis (power spectral density)
- Hands-on experimental skills: assembling and debugging measurement setups
- Rigour in documenting experiments and analysing results
- Autonomy, curiosity and a problem-solving mindset
Benefits:
- 1 day off per month
- Half of transportation cost coverage (as per French law)
- Meal vouchers with Swile, as well as access to a fully equipped and regularly stocked kitchen
Research shows that women might feel hesitant to apply for this job if they don't match 100% of the job requirements listed. This list is a guide, and we'd love to receive your application even if you think you're only a partial match. We are looking to build teams that innovate, not just tick boxes on a job spec.
You will join of one of the most innovative startups in France at an early stage, to be part of a passionate and friendly team on its mission to build the first universal quantum computer!
We love to share and learn from one another, so you will be certain to innovate, develop new ideas, and have the space to grow.
