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: As a Plasma Diagnostics Intern you will work collaboratively to conceive, design, test, and deploy optical diagnostic components and systems that help us understand the performance of our fusion machines. Non-invasive optical probes are essential to our understanding of physical parameters in the core of our plasma and allow us to fine tune the operation of the machine to achieve fusion. We deploy a suite of optical probes that measure a wide range of plasma parameters such as density, temperature, plasma shape, and many more. You Will: - Prototype and bench test optical diagnostics, for example polarimetry or components of optical interferometers - Understand basic operations and bench test potential upgrades to performance (e.g., on polarimetry or interferometry) Required Skills: - Ability to work full time, onsite in Everett, WA for a minimum of 12 consecutive weeks during summer 2027 - Currently pursuing a bachelor’s degree or advanced degree in Physics, Aerospace Engineering, or a related field, with relevant experience in plasma science - Must be able to complete their current degree program and begin full-time employment no later than May 2028 - GPA of 3.0 or above - Basic understanding of benchtop optical test and measurement - Basic proficiency with optical fiber alignment - General optical lab experience/ basic knowledge of laser and laser safety - Proficiency with analysis software such as MATLAB or Python - Optical modeling software skills such as Zemax a plus, but not necessary