Full-Time

Senior Laser & Semiconductor Optical Amplifiers Characterization Engineer

Lightmatter

Lightmatter

201-500 employees

Photonic computing hardware for AI acceleration

Compensation Overview

$210k - $267k/yr

+ Equity Grant + Performance-based Equity

Mountain View, CA, USA

Hybrid

Hybrid role; on-site in Mountain View, CA required.

Master's, PhD

Category
Electrical Engineering (1)
Required Skills
Python
MATLAB
Oscilloscope

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Requirements
  • PhD or Master’s degree in Electrical Engineering, Physics, Applied Physics, Photonics, Optics, or a related technical field.
  • 5+ years of hands-on experience in semiconductor laser, SOA, photonics, or optical device characterization.
  • Strong understanding of semiconductor laser physics, optical gain, carrier dynamics, rate equations, thermal effects, feedback sensitivity, linewidth, RIN, and optical noise mechanisms.
  • Deep hands-on experience with optical and electro-optical lab measurements.
  • Strong familiarity with laser characterization metrics such as threshold current, slope efficiency, wall-plug efficiency, LIV curves, SMSR, RIN, linewidth, wavelength tuning, optical spectrum, power stability, and wavelength stability.
  • Strong understanding of semiconductor optical amplifiers, including gain, saturation behavior, ASE, noise, carrier dynamics, polarization dependence, wavelength dependence, and thermal effects.
  • Experience operating optical and RF instruments, including laser current drivers, TEC controllers, OSAs, optical power meters, photodetectors, RF spectrum analyzers, oscilloscopes, bias tees, optical filters, polarization controllers, optical switches, and fiber-coupled components.
  • Strong Python programming experience for instrument automation, data analysis, plotting, statistical analysis, and automated reporting.
  • Experience using software tools for device design support, modeling, simulation, or data-driven analysis.
  • Strong analytical skills and ability to debug open-ended device, setup, and measurement problems independently.
  • Ability to communicate complex technical results clearly and drive conclusions across design, characterization, packaging, and systems teams.
Responsibilities
  • Lead hands-on characterization of semiconductor lasers, tunable laser sources, DFB lasers, DBR/ECL lasers, laser diodes, and semiconductor optical amplifiers.
  • Measure and analyze key laser and SOA performance metrics, including output power, wavelength, optical spectrum, SMSR, RIN, linewidth, gain, saturation power, ASE, noise figure, tuning behavior, optical stability, wavelength stability, and thermal sensitivity.
  • Develop advanced LIV, L-I-V-T, wavelength tuning, power stability, RIN, SMSR, linewidth, and long-term drift measurement methodologies.
  • Characterize devices across current, voltage, temperature, optical loading, polarization, optical feedback, aging, and operating conditions.
  • Analyze SOA gain, gain saturation, wavelength-dependent gain, polarization-dependent gain, ASE noise, carrier dynamics, thermal behavior, and nonlinear effects.
  • Build, validate, and maintain automated optical and RF measurement setups using Python, PyVISA, LabVIEW, MATLAB, or similar tools.
  • Use modeling and design-analysis software to support characterization planning and data interpretation, including tools for laser physics, optical gain, rate-equation analysis, thermal modeling, optical spectrum analysis, and system-level performance estimation.
  • Develop scripts and software workflows for instrument control, automated data collection, calibration, data processing, visualization, statistical analysis, and automated reporting.
  • Debug complex optical, electrical, RF, and thermal measurement issues, including optical coupling, polarization sensitivity, back-reflection, RF noise, grounding, calibration error, thermal drift, and instrument limitations.
  • Define measurement best practices, calibration procedures, data quality checks, and test documentation standards.
  • Translate characterization results into actionable feedback for laser design, photonics integration, packaging, system architecture, and reliability teams.
  • Support device bring-up from early engineering samples through mature validation and production-readiness phases.
  • Mentor junior engineers and help establish high-quality characterization practices across the team.
  • Prepare clear technical reports, design reviews, data summaries, and recommendations for cross-functional engineering teams.
Desired Qualifications
  • PhD in Electrical Engineering, Physics, Applied Physics, Photonics, Optics, or a related field.
  • Prior experience characterizing DFB lasers, DBR lasers, tunable lasers, ECLs, laser diodes, or SOAs for integrated photonics or optical communication systems.
  • Experience with advanced laser-noise measurements, including RIN, linewidth, phase noise, frequency noise, optical feedback sensitivity, and relaxation oscillation analysis.
  • Familiarity with laser and SOA modeling, including rate-equation modeling, gain modeling, thermal modeling, optical feedback analysis, and wavelength tuning behavior.
  • Experience using commercial or internal simulation/design tools for photonic device analysis, laser design support, or system-level optical performance modeling.
  • Experience with III-V semiconductor materials, heterogeneous integration, laser packaging, fiber coupling, optical isolators, and thermal control.
  • Experience with high-speed optical or RF measurements involving fast photodetectors, RF spectrum analyzers, oscilloscopes, LNAs, bias tees, and calibration/de-embedding.
  • Experience developing automated test platforms for device characterization and validation.
  • Experience analyzing large characterization datasets and creating automated dashboards or reports.
  • Experience supporting reliability, qualification, or production-oriented validation of semiconductor lasers or optical amplifiers.
  • Demonstrated ability to lead technical work independently, define test strategy, mentor junior engineers, and influence cross-functional engineering decisions.

Lightmatter develops photonic computing hardware to speed up AI workloads using light-based processing. Their photonic systems run AI tasks faster and use about 90% less energy than traditional processors. They target AI and autonomous vehicle workloads and collaborate with universities to advance electro-photonic systems. Revenue comes from hardware sales, software licenses, and partnerships, with a goal of bringing scalable photonic computing to market for faster, energy-efficient AI and AV applications.

Company Size

201-500

Company Stage

Series D

Total Funding

$822M

Headquarters

Boston, Massachusetts

Founded

2017

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Simplify Jobs

Simplify's Take

What believers are saying

  • NVIDIA NVLink Fusion integration, announced June 2, 2026, validates Lightmatter’s interconnect roadmap.
  • Guide DR, launched April 27, 2026, targets Q4 2026 sampling and higher rack density.
  • Roy Kim joined March 16, 2026, signaling aggressive scaling from validation to deployment.

What critics are saying

  • Passage L20 samples in late 2026, delaying meaningful revenue and customer proof.
  • CPO manufacturing remains brutal; vClick and Guide DR still depend on partner yields.
  • NVIDIA or hyperscalers can internalize photonic interconnects, collapsing Lightmatter’s standalone moat by 2028.

What makes Lightmatter unique

  • Lightmatter’s Passage and Guide platforms attack AI interconnect bottlenecks with photonics, not electricity.
  • It partners with NVIDIA, Synopsys, GUC, ASE, and OCP, shaping emerging optical standards.
  • Its manufacturing network spans TSMC, GlobalFoundries, Tower Semiconductor, Amkor, and ASE.

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Benefits

Health Insurance

Dental Insurance

Vision Insurance

Life Insurance

Disability Insurance

Health Savings Account/Flexible Spending Account

Unlimited Paid Time Off

Flexible Work Hours

Remote Work Options

Paid Vacation

Paid Sick Leave

Paid Holidays

Sabbatical Leave

Hybrid Work Options

Stock Options

Company Equity

401(k) Retirement Plan

Wellness Program

Mental Health Support

Gym Membership

Phone/Internet Stipend

Home Office Stipend

Commuter Benefits

Training & Development

Conference Attendance Budget

Professional Development Budget

Family Planning Benefits

Fertility Treatment Support

Adoption Assistance

Childcare Support

Elder Care Support

Relocation Assistance

Employee Referral Bonus

Tuition Reimbursement

Professional Certification Support

Mentorship Program

Meal Benefits

Employee Discounts

Company Social Events

Growth & Insights and Company News

Headcount

6 month growth

-3%

1 year growth

-5%

2 year growth

-5%
Yahoo Finance
Jun 3rd, 2026
Lightmatter joins NVIDIA NVLink Fusion ecosystem with photonic interconnects for AI infrastructure

Lightmatter, a photonic computing specialist, has joined NVIDIA's NVLink Fusion ecosystem to deliver high-performance optical connectivity for AI infrastructure. The company will provide Co-Packaged Optics and Near-Packaged Optics products compatible with NVIDIA's optical and SerDes technologies. Lightmatter's bi-directional optical link architecture will create a unified platform for semi-custom AI factories whilst reducing fibre and connector requirements by 50%. The technology enables semi-custom XPUs to connect with NVIDIA switch silicon through Lightmatter's products, creating seamless high-bandwidth connectivity for chips from various suppliers. The partnership combines Lightmatter's Passage CPO solutions with NVIDIA's NVLink Fusion architecture. Analysts view this collaboration as a critical milestone in the maturation of co-packaged optics, providing hyperscalers with a blueprint to overcome traditional I/O bottlenecks and scale AI clusters.

Business Wire
May 21st, 2026
Lightmatter unveils Guide DR: liquid-cooled laser NIC quadruples rack density for AI datacentres

Lightmatter has unveiled Guide DR, a high-density laser network interface card that quadruples rack density compared to conventional external laser small form factor pluggables. The liquid-cooled LNIC relocates the light source from the faceplate into the chassis, solving scaling bottlenecks whilst leveraging existing cooling infrastructure. Built to OCP NIC 3.0 dimensions, a single Guide DR module can support up to 51.2 Tbps of aggregate bandwidth. Four modules in a 1 RU switch tray enable 204.8 Tbps of switching bandwidth, eliminating the need for larger 4 RU chassis with liquid-cooled lasers. The module supplies 200 mW of optical power per fibre across up to 64 fibres, driving 256 lanes at 200G each, with zero front-panel footprint. Guide DR will begin sampling in Q4 2026.

Associated Press
Apr 27th, 2026
Lightmatter hires ex-Google AI director Roy Kim to scale photonic interconnects globally

Lightmatter, a photonic computing company, has appointed Roy Kim as Vice President of Product to lead deployment of its photonic interconnect platform. Kim brings over 15 years of AI infrastructure experience from Google, AMD and NVIDIA. At Google since 2021, Kim served as Director of AI Infrastructure Product Management. He previously led Data Center GPU Product Management at AMD and spent eight years at NVIDIA in AI and high-performance computing roles. At Lightmatter, Kim will oversee product roadmap, management, marketing and strategy. The appointment follows significant product launches, including the Guide light engine in January and the Passage L20 optical engine in March. Lightmatter's technology aims to eliminate data bottlenecks in AI data centres through photonic interconnects.

Business Wire
Mar 11th, 2026
Lightmatter achieves record 1.6 Tbps per fiber with photonic interconnect chiplet

Lightmatter has achieved a record-breaking 1.6 Tbps throughput per fibre with its Passage Co-Packaged Optics chiplet, marking a significant milestone in AI interconnect performance. The technology, developed in collaboration with Qualcomm Technologies, uses a 16-wavelength DWDM architecture and delivers up to eight times more bandwidth per fibre than existing solutions. The silicon-proven platform combines Lightmatter's photonic engine with Qualcomm Technologies' 112G PAM4 optical SerDes chiplet, addressing interconnect bottlenecks limiting AI model scaling. The architecture reduces power consumption whilst enabling connectivity for next-generation processors and switches, with Passage L-Series photonic engines on track to deliver 100 Tbps and beyond. The record-breaking Passage L-Series photonic interconnects are now available through evaluation kits for lead customer testing.

Associated Press
Mar 11th, 2026
Lightmatter launches vClick Optics, first detachable fiber array for high-volume CPO production with <1.5 dB loss

Lightmatter has unveiled vClick Optics, the industry's first detachable fibre array unit for co-packaged optics advanced packaging. The technology enables high-volume manufacturing of 3D CPO-enabled chips by allowing manufacturers to verify optical engines before final integration, reducing yield loss risks. vClick Optics achieves insertion loss below 1.5 dB and supports high-bandwidth Dense Wavelength Division Multiplexing for 32-100Tbps optical interconnects. The technology integrates SENKO's connector solutions with Lightmatter's photonic technology and is compatible with advanced packaging flows from major foundries. Developed in partnership with ASE and SENKO Advanced Components, vClick transforms permanent fibre attachment into a plug-and-play solution. Lightmatter will showcase the technology at the Optical Fiber Communication conference in Los Angeles from 15-19 March 2026.