Senior Design Physicist- Active Security Clearance Required

About the role

We have an opening for a Design Physicist who is an exceptional physical scientist or engineer with a background in fields such as plasma physics, radiation transport, atomic physics, nuclear physics, physical chemistry, condensed matter physics, computational physics, or hydrodynamics.

Our national-security mission encompasses aspects of computational, theoretical, and experimental physics associated with the complex processes of nuclear explosives. Under limited direction, you will be responsible for advancing our understanding and developing methodologies for important national-security challenges. This position is in the Design Physics Division within the Strategic Deterrence Directorate.

This position may offer a hybrid schedule, which includes the flexibility to work from home one or more days per week, after a probationary period. The specifics of the hybrid schedule, including the exact number of days required in the office and virtual work options, may vary based on the needs of the team and the organization.

This position will be filled at either level based on knowledge and related experience as assessed by the hiring team. Additional job responsibilities (outlined below) will be assigned if hired at the higher level.

You will

• Design and provide analysis of complex experiments exploring the physics of nuclear explosives.
• Simulate weapons phenomena and perform weapons assessment and certification tasks using physical models in computer codes.
• Participate in the assessment of foreign nuclear weapon systems.
• Present and disseminate research results at scientific conferences and in peer-reviewed publications, in both open and classified environments, internal and external to LLNL.
• Positively represent the Program and Laboratory demonstrating advanced verbal and written skills.
• Responsibilities may also include interacting with external stakeholders, both at NNSA and across the broader interagency, via offsite assignments.
• Develop expertise in interrelated fields of physics important to weapons assessment and certification.
• Lead independent technical work conducting applied physics research and provide technical guidance and mentoring to less-experienced staff and collaborators as part of a multidisciplinary team.
• Lead top quality research in relevant areas of physics and engineering.
• Problem-solve and make decisions necessary to independently address challenging problems.
• Perform other duties as assigned.

Additional job responsibilities at the SES.4 Level

• Assess the highly complex physics interactions that take place in a nuclear explosion.
• Design and provide in depth analysis of experiments exploring the physics of nuclear explosives.
• Define and implement stockpile stewardship for specific weapons systems.
• Simulate weapons phenomena and perform highly advanced weapons assessment and certification tasks using physical models in computer codes.

Qualifications & Requirements

• This position requires an active Department of Energy (DOE) Q-level clearance or active Top-Secret clearance issued by another U.S. government agency at the time of hire.
• PhD in physics, engineering, or related field or equivalent combination of education and related experience.
• Significant experience conducting applied physics research.
• Record of completing outstanding research in relevant areas of physics and engineering.
• Significant experience with advanced computer-based design and analysis of experiments.
• Aptitude for mastering new fields of physics; a record of creativity, physical insight, and breadth of understanding in advanced applications of complex physical processes.
• Significant experience in using advanced computational facilities for applied physics analysis.
• Advanced verbal and written communication and presentation skills necessary to author advanced technical and scientific reports, publications, invited papers, and to deliver scientific presentations.
• Significant experience working effectively independently and in a multidisciplinary, team-research environment.
• Demonstrated self-motivation and initiative in addressing challenging problems.

Additional qualifications at the SES.4 Level

• Substantial experience presenting and disseminating highly advanced research results at scientific conferences and peer-reviewed publications, in open and classified environments, internal and external to LLNL.
• Substantial experience communicating technical recommendations, results, and programmatic impacts with external sponsors and senior management.
• Substantial experience developing innovative methods to expand knowledge of interrelated fields of highly advanced physics important to weapons assessment and certification.
• Substantial experience establishing broad technical strategy, directing technical tasks and multidisciplinary teams, and influencing technical direction to achieve program goals.

Qualifications We Desire

• Subject matter expert knowledgeable of highly advanced concepts to include experience and ability to lead independent work conducting applied physics research in one or more of the following fields: plasma physics, radiation transport, atomic physics, nuclear physics, and hydrodynamics.
• Significant experience with highly advanced computer-based design and analysis of highly complex experiments.
• Extensive experience at the expert level in the development of principles, theories, concepts, and techniques relevant to applied physics research.

Additional information

Please include a personalized cover letter with your application, highlighting your qualifications and why you're interested in this position.

Pay and benefits

Pay Range $175,530 - $267,060 $175,530 - $222,564 Annually for the SES.3 level $210,630 - $267,060 Annually for the SES.4 level

This is the lowest to highest salary we in good faith believe we would pay for this role at the time of this posting. An employee's position within the salary range will be based on several factors including, but not limited to, specific competencies, relevant education, qualifications, certifications, experience, skills, seniority, geographic location, performance, and business or organizational needs.

Position Information

This is a Career Indefinite position, open to Lab employees and external candidates.

Why Lawrence Livermore National Laboratory?

• Included in 2026 Best Places to Work by Glassdoor!
• Flexible Benefits Package
• 401(k)
• Relocation Assistance
• Education Reimbursement Program
• Flexible schedules (*depending on project needs)

Security Clearance

This position requires an active Department of Energy (DOE) Q-level clearance or active Top Secret clearance issued by another U.S. government agency at time of hire.

Pre-Employment Drug Test

External applicant(s) selected for this position must pass a post-offer, pre-employment drug test. This includes testing for use of marijuana as Federal Law applies to us as a Federal Contractor.

Wireless and Medical Devices

Per the Department of Energy (DOE), Lawrence Livermore National Laboratory must meet certain restrictions with the use and/or possession of mobile devices in Limited Areas. Depending on your job duties, you may be required to work in a Limited Area where you are not permitted to have a personal and/or laboratory mobile device in your possession. This includes, but not limited to cell phones, tablets, fitness devices, wireless headphones, and other Bluetooth/wireless enabled devices.

If you use a medical device, which pairs with a mobile device, you must still follow the rules concerning the mobile device in individual sections within Limited Areas. Sensitive Compartmented Information Facilities require separate approval. Hearing aids without wireless capabilities or wireless that has been disabled are allowed in Limited Areas, Secure Space and Transit/Buffer Space within buildings.

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