The posting
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, and AstraZeneca 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.
Location: Oxford, England, UK Working pattern: Hybrid
Role:
We are looking for a Senior Silicon Validation Engineer to join our Cryo-CMOS IC team at IonQ Oxford. You will lead the validation and characterisation of analogue and mixed-signal ASICs for our trapped-ion quantum processors, from test planning and platform development through first-silicon bring-up, debug and system integration.
This is a hands-on technical role. You will shape our validation architecture, build reusable hardware and software, and provide the evidence needed to make confident silicon acceptance decisions. The work includes room-temperature silicon validation and silicon characterisation at cryogenic temperatures (around 4 kelvin), on packaged parts, chip-on-board assemblies and bare die on a cryogenic probe station.
Responsibilities:
You will own validation delivery across chip and system interfaces, working closely with analogue and digital design, verification, modelling, firmware and systems engineers. You will turn requirements into measurable tests, prepare platforms before silicon arrives and resolve failures across the chip, board and software.
As a Senior engineer, you will set technical standards, guide other engineers and improve coverage, repeatability and test efficiency across successive ASIC generations.
Key responsibilities include:
- Own the silicon validation strategy, plans, acceptance criteria and readiness reviews, with traceability from block and system requirements to tests, results and unresolved risks.
- Present the silicon acceptance report to the Cryo-CMOS IC Lead and programme stakeholders.
- Lead first-silicon bring-up and characterisation of sample-and-hold and switch arrays, DACs, ADCs, references, amplifiers, switches, regulators, clocking and device-level test structures, across supply, temperature, operating modes and device variation, with sound calibration and measurement uncertainty.
- Develop validation boards, fixtures and reusable Python automation, instrument drivers and regression suites, addressing signal integrity, grounding, power integrity and measurement access, with version-controlled tests and reproducible data analysis.
- Plan and lead cryogenic measurements with specialist colleagues, including bare-die probing and the cold signal chain, and drive failures to root cause, separating silicon defects from board, firmware and test artefacts and correlating results with simulations, device models and foundry or partner data.
- Influence testability before tape-out, coordinate validation with external design partners, the foundry and other IonQ sites.
- Lead technical reviews, mentor engineers and document methods to improve throughput, data quality and reuse.
Requirements:
You will bring substantial experience in analogue or mixed-signal silicon validation and characterisation, with ownership of multiple silicon bring-up programmes. A degree in electrical or electronic engineering, or equivalent practical experience, is expected. You should combine hands-on laboratory skills with sound judgement on test coverage, measurement confidence and programme risk.
You’d be a great fit with:
- Strong electronics fundamentals and experience validating precision signal chains, data converters or power-management circuits, including their digital control interfaces.
- Practical expertise with oscilloscopes, precision sources and meters, signal generators, spectrum and logic analysers; confidence designing reliable low-noise, low-leakage measurements.
- Strong Python programming for instrument control, automated testing and statistical analysis; disciplined use of Git or equivalent version control and maintainable test software.
- Experience designing and debugging test PCBs, reviewing layouts and working with interfaces such as SPI, I2C, JTAG and custom shift-register chains, alongside embedded firmware or FPGA-based platforms.
- A record of resolving complex chip, board and software interactions through structured experiments and collaboration.
- Experience leading technical projects, mentoring engineers and communicating evidence, uncertainty and decisions in clear written reports.
Useful additional experience includes cryogenic or other extreme-temperature testing; wafer or bare-die probing; early-stage IP or test-chip evaluation; FPGA development and C/C++; circuit simulation; and production test correlation. Prior quantum computing is welcome but not required.
Benefits:
Be part of a team that’s shaping the future of quantum. We offer more than just a role, you’ll join a world class community of scientists, engineers and innovators working to unlock the full potential of quantum computing.
We offer a range of benefits, including opportunities to further your career alongside industry leaders, a competitive salary with IonQ stock options, an annual performance bonus, generous annual leave, flexible hybrid working, private medical and dental insurance for you and your family, and much more.
Join us and be part of the future of quantum computing.
We’re proud to be an equal opportunity employer and welcome applicants from all backgrounds.
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!
