Efficient Cat Qubit Simulation Intern M/F

Posted: 2026-11-02

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 the Hilbert space grows quickly as soon as several cat-qubit modes are involved, estimating error probabilities in multi-mode operations lies beyond the reach of both brute-force simulation and exact master-equation methods.   The Research Intern — Efficient Cat Qubit Simulation addresses this gap by making such estimates computationally tractable, so that error rates of multi qubit operations can be quantified and better understood.   Reporting to the Device Theorist, you will work closely with the CNOT team to explore how quantum trajectories and tensor-network representations can be combined to estimate error probabilities in many-mode settings.   This internship will start in February 2027 for 6 months!

1. Develop simulation methods for many-mode cat-qubit systems

- Combine tensor-network representations with quantum trajectory unravelings of the Lindblad master equation to simulate multi-mode operations

- Verify the numerical robustness of the simulations (Hilbert-space and bond-dimension truncation, solver stability and precision)

2. Estimate error probabilities and rates

- Extract quantitative estimates of error probabilities and rates from the simulated trajectories

- Assess the statistical reliability of these estimates and their dependence on simulation parameters

3. Validate and benchmark the approach

- Compare estimates against exact master-equation results where they exist and against theoretical predictions

- Quantify the computational cost and scaling of the method relative to standard density-matrix simulation