Senior Experimental Physicist

About Avalanche Energy

Avalanche Energy is a Washington-based startup building compact, deployable fusion systems through rapid hardware iteration. Rather than pursuing fusion as a single grid-scale outcome, Avalanche develops transportable fusion machines designed to be built, tested, and operated on short cycles, turning real hardware into steady progress. This approach enables near-term applications that demand extreme energy density and endurance—starting with fusion neutron production for radioisotope power and other defense and space uses—while advancing the underlying fusion platform.

Backed by U.S. government programs and a team experienced in delivering complex systems, Avalanche is focused on building fusion that runs in the real world, not just on paper.

Avalanche might be a fit for you if:

• You like working at the intersection of plasma theory, simulation, and real hardware, and want your work to directly influence experiments and system design.
• You’re comfortable making progress in ambiguous, fast-moving environments, using good scientific judgment to learn quickly and adjust course.
• You value rigor and clarity as tools that help teams move faster—not as reasons to slow down.
• You enjoy close collaboration with engineers and care about how plasma physics tradeoffs show up in real systems.
• You take satisfaction in mentoring and sharing knowledge to help a strong science team get even better.
• You’re excited by rapid iteration—building, testing, learning, and repeating—and want to help make that loop more effective.

About the Role

A Senior Experimental Physicist is a technical leader and senior individual contributor within Avalanche’s Science organization. This role is responsible for advancing plasma physics understanding as it applies directly to Avalanche’s fusion systems, while operating comfortably in an environment of rapid iteration, incomplete information, and evolving requirements.

This is not a purely academic role. You will work closely with experimental systems, diagnostics, simulations, and cross-functional engineering teams to inform design decisions, interpret results, and guide next experiments. You are expected to exercise strong scientific judgment, propose new approaches, and help the team move faster and smarter—even when the path forward is not fully defined.

In this role you’re responsible for:

• Design, analyze, and interpret plasma experiments in close collaboration with the broader science team and engineers.
• Contribute to rapid test–learn cycles by translating results into clear, actionable recommendations for future experiments.
• Integrate experimental data, simulations, and theory to inform conclusions and guide next steps.
• Help define which questions matter most at a given stage of development and where effort is best focused.
• Work closely with engineering teams (mechanical, electrical, instrumentation, software) to ensure plasma physics considerations are reflected in system design.
• Communicate complex plasma physics concepts clearly to non-plasma specialists across the organization.
• Support product and system trade studies by providing scientifically grounded input.
• Act as a technical mentor to junior scientists and engineers.
• Share knowledge, review analyses, and contribute to a collaborative and curious science culture.
• Help strengthen team practices around documentation, analysis, and communication.

About you:

• PhD in plasma physics or a closely related field, or equivalent depth of experience.
• 3+ years post-PhD experience in a plasma related R&D environment working closely with hardware and diagnostics.
• Demonstrated ability to approach complex plasma physics problems analytically
• Comfortable interpreting theory, simulation, and experimental results .
• Ability to work with a diverse team as well as operate independently, prioritize work, and make progress in ambiguous environments.
• Clear communicator who can explain complex ideas across disciplines.
• Comfort iterating quickly and revising assumptions as new data emerges.
• Comfortable coding in python or similar languages

Bonus skills & experience:

• Direct experience working with fusion relevant plasma diagnostics
• Electrical and/or…