Role
Commonwealth Fusion Systems is hiring a Principal Scientist - Radio Frequency Plasma Heating to commission and operate SPARC's ion cyclotron systems and study radio-frequency physics and engineering for SPARC and ARC. SPARC's only auxiliary heating is a 120 MHz, 25 MW coupled ion cyclotron resonance heating (ICRH) system, and a separate ion cyclotron discharge cleaning (ICDC) system conditions surfaces inside the vessel.
Responsibilities: Simulate the ICRH antennas and RF network, contribute to component testing, and inform the RF control system and operator interfaces. Help develop commissioning and operating plans and procedures, commission ICRH and ICDC into early plasmas, and operate ICRH during high-power deuterium-tritium plasmas. Study RF wave physics in SPARC, feed modelling into ARC design, and work with university and national-lab collaborators.
Requirements: A PhD in plasma physics or a closely related discipline and at least seven years of post-degree experience with radio-frequency heating, current drive or discharge cleaning systems in fusion plasmas, such as ion cyclotron, lower hybrid or helicon systems. Candidates need experience running experiments on tokamaks, stellarators or similar devices, developing hardware for plasma experiments, and using COMSOL, ANSYS HFSS, CST or similar finite-element tools, plus expertise in ICRF, plasma physics, fusion engineering and fusion power plant design.
Preferred experience: More than 10 years operating or simulating RF plasma heating, Python, designing ICRH systems, RF diagnostics and operating tools or procedures, and modelling ICDC physics.
Working arrangements: Candidates must be willing to travel or work required nights, weekends or on-call shifts on a regular basis, and are expected to travel once or twice a year for conferences. Industrial hazards include strong magnets, high voltage and cryogenics. Any offer depends on compliance with U.S. export-control laws.
Snapshot
| Employer | Commonwealth Fusion Systems |
| Workplace | Devens, Massachusetts, US |
| Onsite | Onsite |
| Employment type | Full-time |
| Salary | $150,000–$225,000 a year |
| Date posted | 2026-08-20 |
| Expires | — |
| Verified | 2026-10-06 |
Sources & verification
The original publication date is exactly as posted on the employer ATS — no substitutions. The links below are the same ATS pages we used to verify this listing; the dates come from when we last checked them.
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