Senior Optical Validation Engineer: Lasers & Photonics

CScale; Palo Alto (CA); On-site; USD 150,000 - 250,000; Full time

Benefits offered by this job

Equity

Job summary

CScale is building the interconnect for gigawatt-scale AI. We seek a hands-on optical engineer to validate lasers, silicon photonics, and packaging interfaces, building measurement methods and test stations to ensure parts meet specs and tracing data across labs.

You will drive validation plans, characterize devices in lab settings, and collaborate with photonics, packaging, and supplier teams to enable high‑throughput, low‑loss interconnects for AI workloads.

Qualifications

• Bachelor's degree in Optics, Photonics, Physics, Electrical Engineering, or a related field with 5+ years of relevant industry experience
• Hands-on experience characterizing semiconductor lasers and photonic components in a lab
• Solid understanding of laser physics, Gaussian beam optics, fiber modes, and fiber-to-chip coupling
• Experience with optical test equipment: optical spectrum analyzers, power meters, tunable lasers, polarization controllers, and alignment and positioning stages
• Experience designing experiments and analyzing optical data to find physical root causes, including statistical analysis of component variation
• Python or similar for measurement automation and data analysis
• Clear communicator who works well across engineering disciplines and with suppliers
• Strong ownership mindset with the ability to work in ambiguous and dynamic environments
• MS or PhD in Optics, Photonics, or Physics
• Silicon photonics device characterization experience, including wafer-level probing
• Optomechanical design experience for characterization fixtures
• Experience with fiber array units, micro-lenses, detachable optical connectors, or active alignment
• Experience qualifying optical components

Responsibilities

• Define validation plans, specifications-to-test mapping, and acceptance criteria for laser, silicon photonic, and packaging components and interfaces
• Build and run characterization setups for semiconductor lasers: LIV, optical spectrum, side-mode suppression, wavelength versus temperature and current, relative intensity noise, and modulation and extinction performance
• Characterize silicon photonic devices at die and wafer level: waveguide and coupler loss, modulator and photodetector performance, wavelength-dependent behavior, and thermal tuning response
• Develop precision measurement methods for fiber-to-chip and chip-to-chip interfaces — fiber arrays, micro-optics, edge and grating couplers — including insertion loss, alignment tolerance, and polarization dependence
• Correlate component, wafer, and package measurements with optical models to pinpoint the physical causes of excess loss and performance variation
• Define test structures and measurement requirements for new devices and interfaces with the photonics design and packaging teams
• Establish incoming inspection and sampling plans for supplier parts, and correlate measurements with supplier data and across labs
• Support component-level reliability and burn-in testing in partnership with the reliability team
• Automate measurements and build the data pipelines that make component results traceable from supplier lot to assembled engine
• Communicate findings and recommend design, component, or assembly changes to internal teams and suppliers

Skills

Laser characterization

Gaussian beam optics

Fiber-to-chip coupling

Data analysis

Python automation

Lab measurement techniques

Cross-functional communication

Education

Bachelor's degree in Optics/Photonics/Physics or related field

MS or PhD in Optics/Photonics/Physics

Tools

Optical spectrum analyzers

Power meters

Tunable lasers

Polarization controllers

Alignment and positioning stages

Fiber coupling accessories

Job description

CScale is building the interconnect for gigawatt-scale AI. We seek a hands-on optical engineer to validate lasers, silicon photonics, and packaging interfaces, building measurement methods and test stations to ensure parts meet specs and tracing data across labs.

You will drive validation plans, characterize devices in lab settings, and collaborate with photonics, packaging, and supplier teams to enable high‑throughput, low‑loss interconnects for AI workloads.