Expert Quantum Physicist

Quantum Software; Paris; Hybride; EUR 120 000 - 180 000; Plein temps

Avantages offerts par ce poste

BSPCE plan

Direct IP bonuses

Remote up to 40%

Résumé du poste

Alice & Bob is building the world’s first universal, fault-tolerant quantum computer. We seek a Technical Lead for numerical simulation of superconducting qubits to drive the strategy, set trust criteria, and ensure devices are accurately modeled before lab validation.

You will own the full simulation stack from device physics to numerical implementation, collaborating with physicists, engineers, and experimental teams to deliver robust, trustworthy results and push the company’s quantum

Qualifications

• 7+ years of post-PhD experience in a relevant academic field or industry.
• PhD or equivalent in quantum physics, applied physics, electrical engineering, quantum information, or computational physics.
• Proven track record of technical leadership in simulation or modeling affecting device design.
• Broad mastery across the full simulation stack from device physics to numerical implementation.
• Deep experience simulating superconducting qubits or similar systems and familiarity with HFSS/COMSOL.

Responsabilités

• Own the predictive performance of our simulation stack end to end — accuracy, reliability, and efficiency from device physics through numerical implementation.
• Set the standard for what is considered trustworthy across microwave, quantum, and numerical simulations, including validation practices.
• Find and fix bottlenecks in performance, robustness, or model fidelity.
• Shape the roadmap for our simulation tools in collaboration with domain experts.
• Coordinate with experimentalists to close the loop between simulation and lab results.
• Be the expert reference on simulation methodology across the team.

Connaissances

Quantum physics

Microwave engineering

Numerical methods

Python / NumPy

Formation

PhD in quantum physics or related field

Outils

Ansys HFSS

COMSOL

Palace

QuTiP

Dynamiqs

CUDA-Q

Description du poste

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!

About the mission

We're looking for an experienced physicist to own the numerical simulation strategy for our superconducting qubits: setting direction, defining what counts as a trustworthy result, and identifying where our methods need to improve. Doing this means working across quantum physics, microwave engineering, and numerical methods. It calls for deep understanding of all three, and expertise where they intersect.

About the role.

As technical lead for numerical simulation of superconducting qubits, you'll own how Alice & Bob predicts and validates device behavior before it reaches the lab. You'll define our simulation approach — from microwave design to qubit dynamics — and set the bar for when a result can be trusted. Where our methods fall short, you'll spot it and drive the fix. You're not executing someone else's roadmap; you're setting it, working closely with the physicists and engineers in the details.

About you

You have several years of experience beyond your PhD, with expertise spanning quantum physics, microwave engineering, and numerical methods. When a result doesn't hold up, you're comfortable challenging it and can rigorously demonstrate why. You're motivated by owning a technical direction rather than contributing to one.

Responsibilities

• Own the predictive performanceof our simulation stack end to end — accuracy, reliability, and efficiency from device physics through numerical implementation.
• Set the standard for what "trustworthy" meansacross microwave, quantum, and numerical simulations — defining accuracy, convergence, and validation practices, and leading the theoretical justification of our tools and methods.
• Find and fix what's holding the stack back, whether the bottleneck is performance, robustness, or model fidelity.
• Shape the roadmapfor our simulation tools, working closely with domain experts across the company.
• Close the loop with experiment— validating simulations against measured device performance alongside experimentalists.
• Be the expert referenceon simulation methodology across the team.

Requirements

• 7+ years of post-PhD experience in a relevant academic field or industry.
• PhD or equivalent in quantum physics, applied physics, electrical engineering, quantum information, or computational physics.
• A proven track record of technical leadership: driving simulation or modeling methodology at the organizational level, with results that directly shaped device design decisions.
• Broad, hands-on mastery across the full simulation chain — from device physics to numerical implementation — with recognized, go-to depth in at least one of these areas.
• Deep experience simulating superconducting qubits or comparable systems: finite element methods (Ansys HFSS, COMSOL, Palace), circuit quantization (scQubits, Quantum Metal), and quantum simulation (QuTiP, Dynamiqs, CUDA-Q).
• Command of the underlying quantum physics: circuit QED, Hamiltonian modeling, open quantum systems, decoherence mechanisms, physical gates and measurement.
• Fluency in microwave engineering for quantum applications: passive components (resonators, transmission lines, filters, couplers, circulators), active devices (amplifiers, mixers), and measurement instrumentation (VNAs, spectrum analyzers, homodyne/heterodyne detection).
• Strong software engineering foundations for scientific computing — Python, NumPy/SciPy or JAX, and Git — sufficient to build and maintain simulation infrastructure others rely on.
• The judgment to determine when a simulation result can and cannot be trusted, and the ability to bring teams and domain experts to a shared view on those calls.
• A track record of mentoring senior scientists and engineers, and building consensus among specialists from different fields.

Nice to have

• Hands-on experience with HPC or large-scale simulations.
• Publications in circuit QED or computational electromagnetics.
• Hands-on experience in experimental research, providing a practical sense of how quantum devices behave in the lab — beyond what models predict.

Recruitment Process

• Screening Call with Grace, Talent Acquisition Specialist (30 min)
• Hiring Manager Interview with Mattis (45 min)
• Technical Presentation with the Team (60 min)
• Leadership Team Interview (45 min)
• Fit Interview (45 min)
• Reference check

Benefits:

• - Our success is your success: own it with our BSPCEplan
• - Direct IP Compensation:Earn substantial bonuses for driving the core patents that define our quantum architecture.
• - Flexibleremotepolicy, up to 40 % a month
• - A Parental planincluding additional benefits such as crèche support or additional days-off to take care of under 12 years old children
• - Subsidized membership with Urban Sports Club
• - Mental healthsupport withmoka.care
• - 25-day vacation policy (as per French law) + RTT
• - Half of transportation cost coverage (as per French law), or yearly allowance for the die-hard bicycle users
• - Competitive health coverage, with Alan.
• - Meal vouchers with Swile, as well as access to a fully equipped and regularly stocked kitchen
• - French language courses covered by the company for those interested

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.