Senior Laser Engineer

About OLIX AI is growing faster than any technology in history and the explosion in demand has created a massive infrastructure gap; we can no longer build chips or power stations fast enough to keep up. The industry is still leaning on a ten-year-old hardware blueprint that has reached its limit. A new paradigm that is faster and more efficient will be the biggest economic opportunity of the next century and create the most important company of the next decade. OLIX is building this next paradigm; the Optical Tensor Processing Unit (OTPU) achieves performance and energy efficiency that is impossible to match from existing chips.

The Role: We are seeking a Senior Laser Engineer with deep expertise in VCSEL technology to lead the development of production-grade laser devices for integration into our OTPU systems. This is a device-level role focused on III-V semiconductor lasers, spanning epitaxial design, device architecture, fabrication transfer, characterisation, packaging interaction, and reliability. You will work from first-principles physics through to manufacturable arrays operating at high speed and high density. You will collaborate closely with electronics, optics, packaging, and system architecture teams to ensure that VCSEL performance directly supports system-level bandwidth, power, and reliability targets.

Responsibilities:

• Own the design and development of VCSEL devices and arrays for high-density optical systems
• Define and optimise epitaxial layer structures including quantum wells, DBRs, oxidation layers, and current confinement schemes
• Work with external epitaxy suppliers and foundries to specify, review, and iterate wafer growth runs
• Drive device simulation across optical, electrical, and thermal domains
• Characterise fabricated devices including LIV, spectral behaviour, modulation bandwidth, efficiency, thermal rollover, and reliability
• Develop strategies for current confinement, high-speed modulation, and array uniformity
• Collaborate with electronics teams on driver integration and impedance considerations
• Interface with packaging and optics teams to ensure coupling efficiency, mechanical tolerance robustness, and thermal performance
• Establish reliability methodologies including accelerated life testing and failure analysis
• Contribute to multi-generation device roadmaps aligned with system architecture requirements
• Support transfer from R&D to pilot and volume manufacturing

Skills & Experience:

• 7+ years of experience in semiconductor laser development, with strong emphasis on VCSELs
• Degree in Physics, Electrical Engineering, Materials Science, or related discipline
• Deep understanding of III-V materials systems such as GaAs/AlGaAs or InP-based structures
• Understanding of epitaxial techniques such as MBE or MOCVD
• Deep familiarity with high-speed modulation and bandwidth limitations
• Understanding of thermal management in dense laser arrays
• Experience working with external foundries or epitaxy houses
• Ability to interpret SEM, AFM, and other device-level characterisation data
• Strong cross-functional collaboration skills

Nice to Have:

• Experience with large VCSEL arrays
• Knowledge of reliability standards for datacom applications
• Experience integrating lasers with custom driver ASICs
• Background in yield optimisation and statistical process control
• Python skills

Compensation & Benefits:

• Competitive Salary: £126,000 - £154,000 annual salary commensurate with your experience, skills, and location.
• Equity & Ownership: Meaningful stock options. You're not just joining the mission; you're owning a piece of it.
• Proximity Bonus: We value your time. To minimise your commute and maximise your life, we offer a £24K annual Living-Local Bonus if your residence is within 20 minutes of the office.

Health & Wellbeing:

• Premium Healthcare: Comprehensive BUPA medical and dental cover, including Medical History Disregarded (MHD), for complete peace of mind.
• Time Off: 25 days of annual leave, plus all UK bank holidays.

The Workspace & Tech:

• Elite Hardware: M4 Macs come as standard, with M4 Pro upgrades for our engineering team. We will provide whatever you need to do your best work.
• Optimal Environment: High-spec noise-cancelling headphones and a fully ergonomic workstation designed for deep focus.
• Rapid Prototyping: Access to our high-performance 3D printing lab for work, experimentation, and personal creative projects.

Life at the Office:

• Chef-prepared meals: if you need to work late.
• Caffeine on Us: We've got you covered with a tab at our favourite local coffee shop.

Relocation & Global Mobility:

• Visa Sponsorship: We hire the best in the world. We offer full UK and international visa sponsorship.
• Seamless Relocation: Whether you're moving across the country or across the globe, our dedicated relocation partner provides funding and concierge support to get you settled.

Due to U.S. export control regulations, candidates' eligibility to work at Flux depends on their most recent citizenship or permanent residency status. We are generally unable to consider applicants whose most recent citizenship or permanent residence is in certain restricted countries (currently including Iran, North Korea, Syria, Cuba, Russia, Belarus, China, Hong Kong, Macau, and Venezuela). Applicants who have subsequently obtained citizenship or permanent residency in another country not subject to these restrictions may still be eligible.