Laser Physicist

Number of employees

200

Denver, CO

Posted on: 2025-09-22

Category: energy

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Employment type:

Full time

Experience required:

Intermediate

Salary

Salary not provided

About the company:

Xcimer Energy is a fusion energy company focused on commercializing laser-driven inertial confinement fusion, which it describes as the only scientifically validated form of fusion energy. The company is developing high-energy excimer laser systems designed to ignite fusion reactions using fuel derived from seawater and lithium, with the goal of delivering safe, clean, and affordable electricity that is cost-competitive with fossil fuels and renewables. Its mission centers on decarbonizing energy-intensive sectors such as artificial intelligence infrastructure, desalination, and industrial processes that require firm, always-on, carbon-free power. Xcimer's technical approach relies on electron-beam-pumped excimer lasers combined with a pulse compression technique called Stimulated Brillouin Scattering (SBS), which compresses microsecond laser pulses to nanosecond durations without damaging optics. In 2024 the company broke ground on Phoenix, its first prototype high-energy laser system, located in Denver, Colorado, and announced the start of its operations in June 2026. Phoenix is the first electron-beam-pumped excimer laser built in the private sector in more than two decades and validates key elements of the company's low-cost laser fusion architecture. Xcimer's longer-term target is Athena, which it describes as the world's first laser fusion power plant, expected to deliver 400 megawatts of continuous clean energy by 2035. The company has received a U.S. Department of Energy approval of its fusion power plant preconceptual design and technology roadmap milestone, and collaborates with industrial partners such as TRUMPF Laser SE. With a team of nearly 200 engineers, physicists, and business professionals, Xcimer positions itself as the most technically mature private laser fusion company.

Xcimer Energy leverages decades of research on Inertial Fusion Energy (IFE) combined with groundbreaking new laser architecture. Our mission is to deploy fusion power plants to meet global decarbonization goals as fast as possible. Xcimer has assembled a team of leaders in tough tech, fusion science, and manufacturing with a track record of rapid execution. Supported by leading investors, Xcimer is uniquely positioned to deliver limitless, clean, fusion power to combat climate change. Join us in powering a better world with inertial fusion!
 
This is a full-time, onsite role based at our headquarters in Denver, CO.
 
As a Laser Physicist, you will apply your expertise to design, build, modify, and operate both new and existing pulsed laser systems. You will enhance and optimize these systems, such as improving laser beam quality, and work with vendors to procure necessary hardware devices needed for specific laser upgrades. Additionally, you will assist optics engineers with aligning complex laser beam paths, calibrating laser diagnostics equipment, identifying opportunities to improve current diagnostics, writing requirements, and working with vendors to develop state-of-the-art high-energy laser diagnostics. Part of your responsibilities will include maintaining laser systems, which involves realignment, diagnosing issues, and coordinating with vendors to resolve component malfunctions and quickly bring the system back online. You will also conduct spectroscopic experiments, collect and process data, and collaborate closely with experimentalists, theorists, optics engineers, and controls engineers to ensure the system runs reliably and supports experimental needs.
 
We are looking for our scientists and engineers to apply their technical expertise, problem solving skills, and dedication to quality to positively impact the future of energy!          

Equal Employment Opportunity
Xcimer Energy is proud to be an Equal Opportunity/Affirmative Action Employer and is committed to attracting, retaining, and developing a highly qualified, diverse, and dedicated work force. Xcimer Energy hires and promotes people on the basis of their qualifications, performance, and abilities. We support the establishment and maintenance of a workplace that fosters trust, equality, and teamwork, in which all employees recognize and appreciate the diversity of individual team members. We provide all qualified applicants for employment and employees with equal opportunities for hire, promotion, and other terms and conditions of employment, regardless of their race, color, religion, gender, sexual orientation, gender identity, national origin/ethnicity, age, physical or mental disability, genetic factors, military/veteran status, or any other status or characteristic protected by federal, state, and/or local law. Xcimer Energy will consider for employment qualified applicants with criminal histories in a manner consistent with applicable federal, state, and local laws. For more information on “EEO Is the Law,” please see here and here.
 
Benefits
Benefits Employee Benefits include: Medical, dental, vision, basic and supplemental life insurance, paid parental leave (must be employed at time of birth or adoption), short and long-term disability, 401(k) with a company match of up to 6%. Paid Time Off: 15 days per year based on weekly scheduled hours, 10 paid sick leave, and 13 company-paid holidays for all regular employees (including part-time), fixed-term, and interns. Equity will be granted to eligible employees. Equity is designed to allow employees to share in company results and success.

Responsibilities

  • Design, modify, operate, and maintain advanced pulsed laser systems.
  • Enhance laser beam quality by specifying, sourcing, and installing optical components and hardware.
  • Select optical components based on laser damage thresholds, transmission, and beam quality requirements; collaborate with vendors to refine specifications and procure these optics.
  • Develop clear procedures and documentation for technicians, providing training on complex laser systems to enable basic maintenance and alignment tasks.
  • Plan, execute, and oversee spectroscopic experiments, ensuring accurate data collection and thorough analysis.
  • Calibrate laser characterization devices and ensure experimental data is acquired accurately and free of artifacts.
  • Collaborate closely with engineers, offering clear technical guidance to support the design and development of laser systems.
  • Qualifications

  • BS with 3+ years of experience, MS with 1-2 years of related lab experience, PhD desired.
  • Advanced knowledge in solid state and gas pulsed lasers and characterization of laser pulses.
  • Ability to own and maintain complex laser systems.
  • Experience in specifying, budgeting, purchasing, installing, and operating laser systems, detectors, optics, spectrometers, and other scientific research equipment.
  • Experience in nonlinear frequency conversion processes.
  • Independent troubleshooting and solving non-trivial technical issues.
  • Planning, managing, and executing laser-based experiments.
  • Experience working with a multidisciplinary team of engineers and scientists.
  • Highly self-motivated, with the ability to work independently without guidance.
  • Advanced verbal and written communication skills.
  • Must be a U.S. citizen or national, U.S. permanent resident (current Green Card holder), or lawfully admitted into the U.S. as a refugee of granted asylum.
  • Desired

  • PhD in electrical engineering, chemistry, physics, or related fields.
  • Expertise in optical spectroscopy, gas kinetics, and data processing.
  • Experience in laser gain dynamics
  • Experience with electro-optical devices.
  • Experience in pulse shaping of laser pulses.
  • Experience in spectral shaping of laser pulses.
  • Hands-on experience with aligning Ti:Sapphire laser systems.
  • Familiarity with fiber optics.
  • Experience working with high-damage-threshold optics.
  • Knowledge of phase mask and/or free-form optic manufacturing, specification, and alignment.
  • Experience with ns and fs pulse diagnostics and characterization (spectral and temporal).
  • Experience with vacuum systems.
  • Experience leading teams of optical, laser, and controls engineers
  • Experience building laser beamlines
  • Experience working in multidisciplinary research laser facilities, such as national labs
  • Experience in writing scientific papers.
  • Experience in Matlab, Python, and LabVIEW.
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