Quantum Physicist, AMO & Quantum Theory

Infleqtion
is on a mission to commercialize atom-based quantum technologies that deliver orders-of-magnitude improvements in sensing and computing applications. As a deep-tech startup, we embrace a results-driven, fast-paced, and customer-focused approach to innovation. We are seeking self-motivated, energetic individuals with exceptional problem-solving and technical skills to help drive our Quantum Computing mission forward. For this theory-focused role, we encourage applications from physicists with expertise in theoretical or experimental
Atomic, Molecular, and Optical (AMO) physics
, particularly those with experience in the coherent control of quantum systems and design and characterization of quantum gates.

• Develop theoretical models of neutral-atom quantum systems to inform system architecture, gate design, and hardware requirements.
• Work closely with experimental physicists and hardware engineers to translate physical models and performance targets into actionable system and subsystem requirements.
• Analyze and quantify error mechanisms in quantum gates (e.g., decoherence, control errors, crosstalk, laser and atomic noise).
• Design, simulate, optimize, and contribute to validation of protocols for quantum gates, calibration, error-mitigation, and compilation to improve fidelity, robustness, and scalability.
• Build and maintain simulation, analysis, and optimization software used to predict system behavior and guide experimental design.
• Support experimental efforts by interpreting data, diagnosing unexpected behavior, and proposing theory-driven mitigation or design changes.
• Self-start and execute new theoretical and modeling efforts given well-defined goals and constraints; scope problems, prioritize approaches, and deliver results on realistic timelines.
• Mentor and teach junior team members as indirect reports. Supervise interns.

• PhD in atomic physics, quantum physics, theoretical physics, or a related field; or equivalent related professional experience (4+ years). If you have substantially more experience than this and are excited to apply, please do! We will also consider hiring at the
  Senior Quantum Physicist level.
• Strong background in AMO physics and quantum mechanics, including atom–light interactions.
• Demonstrated experience modeling and analyzing error mechanisms in quantum systems and quantum gates using analytical methods and numerical simulations, and translating insights into improved designs.
• Proficiency in scientific programming (Python required; experience with numerical, optimization, or simulation libraries preferred).
• Ability to collaborate closely with experimental physicists and hardware engineers, translating between theoretical models, experimental results, and system-level requirements.
• Excellent verbal and written communication skills, with the ability to clearly convey complex theoretical concepts to technical and non-technical audiences.
• Strong problem-solving skills and the ability to rapidly learn and apply new concepts.
• The ability to independently plan and execute new theoretical efforts given high-level goals and constraints.
• Ability to work effectively in a collaborative, agile team environment where engagement, feedback, and shared ownership are essential to success.

It is a plus if you have:

• Experience with neutral-atom quantum computing, Rydberg-based entangling gates, and/or optical tweezer arrays.
• Experience modeling open quantum systems, noise processes, and decoherence in realistic experimental settings.
• Experience with quantum optimal control techniques for high-fidelity quantum gates.
• Familiarity with calibration, benchmarking, and characterization protocols for quantum gates and quantum processors.
• Experience working closely with experimental teams to iterate between theory, simulation, and laboratory results.
• Familiarity with Git, Linux, and command-line tools for collaborative scientific software development.
• Enthusiasm for staying up-to-date with the latest developments in AMO physics and quantum information, and for reviewing relevant literature for the team.