Staff Physicist Jobs (NOW HIRING)

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. We encourage applications from experimental physicists with expertise in Atomic, Molecular, and Optical (AMO) physics, particularly those with experience in the coherent control of quantum systems such as ultracold atoms, trapped ions, and diamond NV centers.

Role and Responsibilities

The responsibilities below represent the core scope of the role and may evolve based on business and program needs. This is a hands-on technical leadership role. Staff Quantum Physicists at Infleqtion remain deeply engaged in system development and operation while also providing technical direction, developing team members, and, where applicable, managing a small team. Depending on program needs, a Staff Quantum Physicist may lead the development of a hardware system or provide technical leadership across multiple teams.

• Lead the design, integration, calibration, operation, and improvement of neutral-atom quantum computing systems and critical subsystems.
• Translate program goals into technical requirements, experimental plans, performance targets, and technical direction across quantum processor design, Rydberg excitation, gate protocols, laser systems, calibration, and system integration.
• Design and analyze experiments and physics-based models to improve gate fidelity, stability, availability, and processor performance; guide architecture and engineering tradeoffs.
• Own critical systems through validation, troubleshooting, performance tuning, reliability improvement, and documentation; translate complex R&D objectives into prioritized work and drive cross-functional delivery.
• Develop Python-based tools in Linux environments for experiment control, data analysis, calibration, automation, and operational support.
• Review technical work and uphold team standards and best practices.
• Manage up to six direct reports, including expectations, performance, coaching, and career development.
• Contribute to hiring, proposals, intellectual property, technical roadmaps, and external technical discussions.

Requirements

• PhD in atomic, optical, AMO, quantum physics, or a related field, or equivalent professional experience; typically 5+ years of relevant post-PhD experience or comparable experience leading complex quantum, atomic, optical, or precision-measurement systems.
• Deep hands-on experience designing, operating, or improving complex AMO or coherent-control experiments, with strong knowledge of atom-light interactions and technologies such as lasers, optical systems, acousto-optic or electro-optic modulators, RF instrumentation, and ultra-high-vacuum systems.
• Proficiency with Python for experiment control, data analysis, automation, or hardware integration, plus working knowledge of Linux, command-line tools, and version control.
• Demonstrated ability to turn ambiguous technical goals into executable plans and validated outcomes, lead system-level work across disciplines, and communicate effectively with specialist and non-specialist audiences.

 It is a plus if you have:

• Experience with neutral-atom quantum computing, Rydberg physics, optical-tweezer arrays, quantum-gate characterization and optimization, or related processor architectures; familiarity with physical error mechanisms and quantum-error-correction requirements.
• Experience with advanced laser and optical systems, including short-wavelength lasers, beam delivery and shaping, optical projection, high-NA imaging, noise mitigation, feedback control, and subsystem stabilization.
• Experience integrating optical, electronic, vacuum, control, and software subsystems into complex experimental platforms.
• Demonstrated technical leadership through mentoring, cross-team coordination, and delivery of complex technical programs; experience contributing to proposals, patents, roadmaps, customer discussions, or government-funded R&D.

Note

This position may require access to information protected under U.S. export control laws and regulations for quantum computing technology. Please note that any offer for employment may be conditioned on authorization to receive software or technology controlled under these U.S. export control laws and regulations without sponsorship for an export license.

WORKING CONDITIONS and PHYSICAL REQUIREMENTS

Work will normally be performed in an office and laboratory environment and around technical equipment including computers and lasers.  We ask that candidates be able to efficiently use automated office equipment such as laptops, copiers, and printers; able to effectively engage in communications (via phone, computer, or in-person).  Any required Personal Protective Equipment will be provided and must be properly used in accordance with company requirements.

TRAVEL

Up to 10% travel may be required.

Benefits

The targeted salary range for this role is $166,000 to $256,000 on an annualized basis plus eligibility to participate in our annual incentive plan.

In addition to your base compensation, we offer a generous Total Rewards program which includes:

• 100% company paid Employee coverage for Medical, Dental, Vision, and Short/Long Term Disability insurance programs
• Employer funded Health Savings Account
• Unlimited Paid Time Off
• 401(k) Matching Programs
• Company paid Life and AD&D Insurance
• Flexible Healthcare Savings Account
• Paid FMLA Leave
• Paid Maternity/Paternity Leave
• Employer Assistance Program
• Student Loan Repayment

Equal Opportunity

Here you have freedom to embrace your whole self: who you love, your gender identity and expression, skin color, age, appearance, disability, neurodiversity, DNA, military/veteran status, citizenship, and other factors that make up who you are. Your uniqueness is valued, welcomed, and appreciated here. We are dedicated to providing a positive workplace and base all employment decisions on your qualifications, performance, merits, as well as business needs. We are proud to be an Equal Employment Opportunity Employer.

Contact Information

If this opportunity interests you and you fit the job description, please submit an application. If you need assistance or an accommodation due to disability, please feel free to contact us at hr@coldquanta.com.

Notice to Recruitment Agencies:

Infleqtion does not accept unsolicited resumes from agencies. Infleqtion is not responsible for any fees related to unsolicited resumes.