Postdoctoral Research Associate, MPEX Boundary and PMI Modeling

About the role

We are seeking a Computational Physicist to carry out modeling of plasma transport and plasma-material interactions (PMI) in the Materials Plasma Exposure eXperiment (MPEX), a high-flux superconducting linear plasma facility nearing completion at ORNL. The candidate will utilize state-of-the-art 3D plasma boundary simulation tools as part of the MPEX Whole-Device Model, working closely with the experimental team to understand this device’s PMI physics and optimize performance of the device in its upcoming campaigns. The position resides in the Power Exhaust and Particle Control (PEPC) group of the Fusion Energy Division at Oak Ridge National Laboratory. The PEPC group performs experimental and modeling work, focused on the boundary region of tokamaks, stellarators, and linear devices, for present-day and future fusion facilities worldwide.

Responsibilities

• Perform interpretive three-dimensional boundary plasma simulations of MPEX, in order to inform and optimize radiofrequency (RF) power coupling, PMI target conditions, and overall device performance in preparation for early device operations.
• Integrate boundary plasma simulations with impurity transport models to assess the production and transport of in-vessel impurities in MPEX operating scenarios.
• Perform predictive modeling to inform the design of new MPEX target geometries, with a focus to improve access to divertor-relevant target exposure conditions.
• Validate simulation results against experimental data and constrain code inputs to reduce uncertainty in predictions for future experiments and guide improvements to the physics model.
• Work closely with teams of diagnosticians, theorists, applied mathematicians, and experimental plasma physicists.
• Create high impact research results to report in peer-reviewed journals and present at scientific conferences.
• Maintain commitment to the implementation and perpetuation of ORNL values and ethics.
• Deliver ORNL’s mission by aligning behaviors, priorities, and interactions with our core values of Impact, Integrity, Teamwork, Safety, and Service.
• Promote equal opportunity by fostering a respectful workplace – in how we treat one another, work together, and measure success.

Requirements

PhD in Plasma Physics, Electrical Engineering, Nuclear Engineering, or a closely related field completed within the last 5 years, or expect to complete a PhD by June 30th, 2027.

This is a temporary 24‑month position, with potential for extension subject to performance and funding availability. Employment requires a Real ID‑compliant form of identification and the ability to obtain and maintain a federal Personal Identity Verification (PIV) card (including a favorable Tier 1 background check). Candidates must have resided in the U.S. for three consecutive years to be eligible for the PIV credential; otherwise a Local Site Specific Only (LSSO) risk determination is required initially.

Qualifications

• Experience with boundary and divertor plasma physics, and use of codes such as EMC3‑EIRENE, SOLPS, UEDGE, SOLEDGE, or similar.
• Experience with plasma‑material interactions, including models for sputtering, impurity transport, and sheath physics.

Skills

• Programming experience in Python, MATLAB, Fortran, C++ and other science‑relevant languages.
• Ability to work individually and/or as part of a team, set priorities to accomplish multiple tasks within deadlines, and adapt to ever‑changing needs.
• Excellent oral and written communication skills for interactions with research staff, peer reviewers, sponsors, and for preparing reports, proposals, and presentations.

Benefits

ORNL offers competitive pay and benefits programs, including medical and retirement plans, flexible work hours, on‑site fitness, banking, and cafeteria