About Helion We are a fusion power company based in Everett, WA, with the mission to build the world's first fusion power plant, enabling a future with unlimited clean electricity. Our vision is a world with clean, reliable, and affordable energy for everyone. Since Helion's founding in 2013, we have raised $1.5 billion from long-time investors such as Sam Altman, Mithril, and Capricorn Investment Group as well as new investors including Thrive Capital, LightSpeed Venture Capital, SoftBank, and others to propel us forward. Our current prototype, Polaris, has reached record-breaking plasma temperatures of 150 million degrees Celsius (13 keV). Helion is continuing to iterate and on the path to the world's first fusion power plant, Orion. This is a pivotal time to join Helion. You will tackle real-world challenges with a team that prizes urgency, rigor, ownership, and a commitment to delivering hard truths – values essential to achieving what no one has before. Together, we will change the future of energy, because the world can't wait. What You Will Be Doing: Helion is hiring an Experimental Scientist to support the development, deployment, calibration, and operation of plasma diagnostics for Helion’s fusion generators. In this role, you will contribute to hands-on experimental work across plasma diagnostics, test campaigns, and high-vacuum systems while partnering closely with scientists, engineers, machine operators, and data teams. This is an onsite role that reports directly to our Director of Plasma and Nuclear Science at our Everett, WA office. You Will: * Support the design, build, deployment, calibration, and commissioning of plasma diagnostic systems for Helion’s fusion generators, operating with autonomy on defined tasks and workstreams while escalating technical risks or tradeoffs when appropriate * Contribute to the operation and troubleshooting of plasma diagnostics used to evaluate plasma parameters such as density, temperature, current profiles, and other key performance indicators * Work cross-functionally with plasma physics, machine operations, controls, mechanical engineering, electrical engineering, and data science teams to support diagnostic readiness for experimental campaigns and testbeds * Develop hands-on expertise in pre-ionization plasma diagnostics, helping establish consistent methods and practices that support next-generation fusion device development * Analyze diagnostic data to identify trends, support experimental interpretation, and inform operational tuning, hardware improvements, or follow-up testing * Document experimental procedures, calibration methods, test results, and lessons learned to improve consistency, reliability, and knowledge sharing across Helion’s experimental programs Required Skills: * Ph.D. in physics, electrical engineering, aerospace engineering, or a related discipline, with a focus on plasma science, diagnostics, or high-vacuum instrumentation * Relevant hands-on experience with plasma systems, advanced laboratory environments, high-vacuum systems, pulsed-power systems, or complex experimental hardware * Experience supporting the design, build, calibration, troubleshooting, or operation of plasma diagnostics such as interferometry, spectroscopy, Langmuir probes, magnetic coils, electrostatic diagnostics, optical diagnostics, or related measurement systems * Ability to operate autonomously on day-to-day technical tasks, apply critical thinking across multiple inputs, and escalate issues appropriately when technical risk, scope, or priority requires broader alignment Benefits Our total compensation package includes benefits, including but not limited to: * Medical, Dental, and Vision plans for employees and their families * 31 Days of PTO (21 vacation days and 10 sick days) * 10 Paid holidays, plus company-wide winter break * Up to 5% employer 401(k) match * Short term disability, long term disability, and life insurance * Paid parental leave and support (up to 16 weeks) * Annual wellness stipend Helion is an equal opportunity employer and value diversity at our company. We do not discriminate based on race, religion, color, national origin, gender, sexual orientation, age, marital status, veteran status, or disability status. If you need assistance or an accommodation during the interview process, please let us know.