Senior Mechanical Engineer

About IonQ: 

IonQ, Inc. [NYSE: IONQ] is the world’s leading quantum platform and merchant supplier - delivering integrated quantum solutions across computing, networking, sensing, and security. IonQ’s newest generation of quantum computers, the IonQ Tempo, is the latest in a line of cutting-edge systems that have been helping customers and partners including Amazon Web Services,andAstraZeneca achieve 20x performance results and accelerate innovation in drug discovery, materials science, financial modeling, logistics, cybersecurity, and defense. In 2025, the company achieved 99.99% two-qubit gate fidelity, setting a world record in quantum computing performance.

Headquartered in College Park, Maryland, IonQ has operations in California, Colorado, Massachusetts, Tennessee, Washington, Italy, South Korea, Sweden, Switzerland, Canada, and the United Kingdom. Our quantum computing services are available through all major cloud providers, while we also meet the needs of networking and sensing customers across land, sea, air, and space. IonQ is making quantum platforms more accessible and impactful than ever before.  

What to Expect

We are seeking a Senior Mechanical Engineer to join our R&D team in Geneva. In this hands-on role, you will design, validate, and continuously improve mechanical enclosures and subsystems that integrate optical and electronic components for our quantum products.

You will take ownership of mechanical solutions from early prototyping through to industrialized product release, with a strong focus on delivering compact, robust, and cost-effective designs. Your work will ensure compliance with dimensional, thermal, and manufacturability requirements, including for highly demanding applications such as cryogenic systems.

What You'll be Doing

You will be responsible for the mechanical development of cutting-edge quantum systems, translating requirements into detailed designs and verified assemblies. This includes 3D modelling and documentation, engineering calculations and simulations, and hands-on testing to validate thermal dissipation and mechanical performance. You will collaborate closely with optical, electronic, and system engineers to optimise interfaces and block specifications, and you will engage with external suppliers to prototype and manufacture parts efficiently. As a senior contributor, you will help improve design practices, promote a rigorous engineering approach, and support multiple projects as a mechanical subject-matter expert.

• Own mechanical design from prototype to industrialised product, including CAD documentation, assembly bring-up, and validation testing
• Drive thermal management (heat sinking, conduction/convection, interfaces and materials), dimensional stability, and manufacturability through design, simulation, and optimization, working closely with cross-functional teams and suppliers
• Perform thermal simulation to predict temperatures, gradients, and heat flows; correlate models with lab measurements and iterate designs and their optimization accordingly

What you'll Bring

We are looking for a candidate with a Bachelor’s or Master’s degree in Mechanical Engineering, Microtechnology, or equivalent, and at least five years of relevant experience in mechanical design and product development. You have hands-on experience designing with sheet metal and/or machined parts, and a strong ability to develop thermal dissipation solutions for compact systems. Familiarity with cryogenic systems is an advantage.

You are rigorous, organised, and proactive, able to work independently while collaborating effectively in a multidisciplinary and Agile environment. Strong communication skills are essential, with fluency in English required; French is considered a plus.

• Solid mechanical engineering foundation with proven experience delivering compact, industrial-grade designs
• Structured, collaborative engineer with strong communication skills and a hands-on approach to validation
• Knowledge of applicable norms and compliance requirements, including EMC and electrical/product safety aspects

You'll be a great fit if:

You bring a track record of taking ownership of mechanical subsystems across multiple development phases-requirements, design, verification, and industrialisation-and you are comfortable acting as the mechanical reference point within a multidisciplinary R&D team. Experience with compact thermal management and exposure to cryogenic constraints are strong assets.

Compensation will vary based on individual factors such as education, qualifications, and experience of the final candidate(s), specific office location, and calibration against relevant market data and internal team equity. Posted base salary figures are subject to change as new market data becomes available. Our benefits include comprehensive medical, dental, and vision plans, matching 401(k), unlimited PTO and paid holidays, parental/adoption leave, legal insurance, and a home technology stipend. Details of participation in these benefit plans will be provided when a candidate receives an offer of employment. 

At IonQ, we believe in fair treatment, access, opportunity, and advancement for all while striving to identify and eliminate barriers. We empower employees to thrive by fostering a culture of autonomy, productivity, and respect. We are dedicated to creating an environment where individuals can feel welcomed, respected, supported, and valued.

We are committed to equity and justice. We welcome different voices and viewpoints and do not discriminate on the basis of race, religion, ancestry, physical and/or mental disability, medical condition, genetic information, marital status, sex, gender, gender identity, gender expression, transgender status, age, sexual orientation, military or veteran status, or any other basis protected by law. We are proud to be an Equal Employment Opportunity employer.

US Technical Jobs.  The position you are applying for will require access to technology that is subject to U.S. export control and government contract restrictions.  Employment with IonQ is contingent on either verifying “U.S. Person” (e.g., U.S. citizen, U.S. national, U.S. permanent resident, or lawfully admitted into the U.S. as a refugee or granted asylum) status for export controls and government contracts work, obtaining any necessary license, and/or confirming the availability of a license exception under U.S. export controls.  Please note that in the absence of confirming you are a U.S. Person for export control and government contracts work purposes, IonQ may choose not to apply for a license or decline to use a license exception (if available) for you to access export-controlled technology that may require authorization, and similarly, you may not qualify for government contracts work that requires U.S. Persons, and IonQ may decline to proceed with your application on those bases alone.  Accordingly, we will have some additional questions regarding your immigration status that will be used for export control and compliance purposes, and the answers will be reviewed by compliance personnel to ensure compliance with federal law.  

US Non-Technical Jobs.  Due to applicable export control laws and regulations, candidates must be a U.S. citizen or national, U.S. permanent resident (i.e., current Green Card holder), or lawfully admitted into the U.S. as a refugee or granted asylum. Accordingly, we will have some additional questions regarding your immigration status that will be used for export control and compliance purposes, and the answers will be reviewed by compliance personnel to ensure compliance with federal law.

If you are interested in being a part of our team and mission, we encourage you to apply!