About Commonwealth Fusion Systems:    Commonwealth Fusion Systems is on a mission to deliver the urgent transition to fusion energy.   Combining decades of research, top talent, and new technologies, we’re designing and building commercially viable fusion power plants. And we're working with policymakers, suppliers, and many others to build the energy industry of the future.   We’re in the best position to make it happen. Since 2018, we’ve raised $4 billion of capital, making us the largest and leading fusion company in the world.   Now we’re looking for more thinkers, doers, builders, and makers to join us. People who’ll bring new perspectives, solve tough problems, and thrive as part of a team.    If that’s you and this role fits, we want to hear from you. Join the power movement as a Staff Scientist - Plasma Material Interaction The plasma facing components (PFCs) in SPARC and ARC are the hardware interface between high performance burning plasmas and the entire tokamak.  Due to the extreme plasma conditions needed for fusion, the PFCs will see heat and particle loads that far exceed most other domains of science and engineering.  The Scientist - Plasma Material Interaction (PMI) provides a critical interface between plasma physics, materials science, and nuclear engineering.  The Scientist will be organizationally based in the Plasma Physics Department with designated technical contacts in the Materials Science and Nuclear Engineering Departments.  By connecting computational plasma physics models, engineering models, neutronics models, and material models, the Scientist will enable predictive modeling of the coupled evolution of PFC materials and the plasma, across timescales ranging from seconds to years.  The ultimate objective of these coupled workflows is to inform the design and operation of the plasma facing components for ARC, a 400MWe fusion power plant to be delivered in the early 2030s.  In order to validate and verify the workflows, the Scientist will oversee test campaigns at experimental facilities around the world, exploring PMI and neutron loading.  Additionally, the Scientist will have access to Deuterium-Tritium experimental data from the SPARC tokamak, and the predictive workflows will be benchmarked using this CFS data.  It is expected that through the aforementioned efforts the Scientist will develop a deep understanding of the material degradation associated with plasma loading and fusion neutron irradiation, and will represent CFS as a world expert in this domain. What you'll do: • Build computational workflows to predict PFC material degradation under plasma loading conditions, and subsequent impact on plasma performance • Build computational workflows to predict PFC material degradation under neutron irradiation • Support ARC design team by running predictive models to inform PFC material lifetime estimates, component shaping, and consequences of overloading • Conduct experimental tests of candidate ARC materials at test facilities around the world, including PMI, heat loads, and neutron irradiation • Leverage SPARC experimental data to benchmark predictive models used for ARC design and optimization • Develop interpretive models used to infer PFC material state from power plant relevant diagnostics • Serve as a bridge between the Plasma Physics Department, Materials Science Department, and Nuclear Engineering Department at CFS • Manage collaborations with universities, national labs, and private companies, around the world • Present scientific results at technical conferences and in a peer reviewed publications What we’re looking for: • PhD or equivalent in plasma physics, materials science, nuclear engineering, or related, with demonstrated research in plasma material interactions • Working knowledge of plasma material interactions, specifically within the context of magnetically confined plasmas (e.g. heat and particle loads, sputtering and erosion, dust formation, PMI diagnostics) • Working knowledge of multiscale material evolution under plasma and/or neutron loading (e.g. PKA and displacement damage, defect and gas-bubble kinetics, transmutation effects, microstructural evolution, surface morphology, and resulting thermomechanical property degradation) • Experience with at least two of the following calculations:  ion energy angle distribution (hPIC or equivalent), binary collision approximation (e.g. RustBCA, SDTrimSP, F-TRIDYN), cluster dynamics or rate theory (Xolotl or equivalent), finite element (e.g. ANSYS, MOOSE, COMSOL) • Experience designing and executing test campaigns at plasma-material exposure devices (e.g. Magnum-PSI, MPEX) and/or high heat flux facilities (e.g. GLADIS, HADES) • Experience with Python, C++, or similar • Version control with git or similar • HPC using Slurm, AWS, or equivalent • Excellent writing and technical communication skills Bonus points for: • Experience with PMI-specific codes: (e.g. ERO2.0, WallDYN, FESTIM, HEAT) • Knowledge of boundary plasma physics and experience with edge/neutral transport codes (e.g. SOLPS-ITER, EMC3-EIRENE) • Experience with neutron or ion-beam irradiation campaigns and post-irradiation examination (e.g. HFIR, ATR) • Experience with materials characterization (e.g. thermal desorption spectroscopy, SEM/TEM) • Knowledge of irradiation damage metrics (e.g. dpa, appm He/dpa) and the limits of fission and ion beam surrogates for fusion neutron spectrum • Knowledge of tungsten metallurgy, processing, and joining • Knowledge of degradation and failure mechanisms in tungsten from plasma and neutron exposure (e.g. recrystallization, embrittlement, DBTT shift, erosion) • Demonstrated ability to build and maintain coupled multi-code computational workflows • Experience containerizing codes (eg Docker, Apptainer) Must-have Requirements: • Perform extended activities such as typing, standing, sitting, etc. • Willingness to travel or work required nights/weekends/on-call occasionally • Work in a facility that contains industrial hazards including heat, cold, noise, fumes, strong magnets, lead (Pb), high voltage, high current, pressure systems, and cryogenics #LI-Onsite At CFS, we excel in fast-paced environments, driven by our values of integrity, execution, impact, and self-critique. As we grow, we’re eager to bring on mission-driven folks who offer diverse perspectives and fresh ways to tackle challenges.   We value diversity deeply and are proud to be an equal opportunity employer by choice. We consider all qualified applicants equally, regardless of race, color, national origin, ancestry, citizenship status, protected veteran status, religion, physical or mental disability, marital status, sex, sexual orientation, gender identity or expression, age, or any other basis protected by law.   This role requires compliance with U.S. laws concerning the export of controlled or protected technologies or information (collectively, “Export Control Laws"). Any offer of employment will be contingent on the need for compliance with such Export Control Laws.