Senior Photonics Circuit Design Engineer

Job Title

Senior Photonics Circuit Design Engineer

Role Summary

Design and deliver high-fidelity behavioral and compact models for silicon photonic and analog sub-circuits used in laser modules and optical interconnects. Support system-level simulations by producing well-correlated models and sub-circuit assemblies that capture process variation, dispersion, thermal effects, and device non-idealities.

Experience Level

Senior - expects several years of relevant industry experience; staff-level candidates will typically have substantially more experience and demonstrated leadership in photonic circuit modeling.

Responsibilities

Own modeling and simulation deliverables that enable system architects and device/circuit teams to predict performance and guide design decisions.

• Develop and maintain compact and behavioral models for active and passive silicon photonic elements (waveguides, couplers, MZIs, microrings, multiplexers, modulators, detectors, thermal tuners, III-V/SOA elements).
• Incorporate process variation, dispersion, thermal-optical tuning, and non-linear effects into component models.
• Partner with device engineers to extract and calibrate model parameters using optical solvers and foundry PDKs; correlate models to silicon measurements across tapeouts.
• Assemble and deliver sub-circuit simulations for laser modules (sources, wavelength control loops, power distribution, monitors, analog interfaces) and Passage interconnect blocks (modulated ring arrays, filter banks, MUX/DEMUX, receiver front-ends).
• Refine topologies against KPIs such as insertion loss, extinction ratio, isolation, tuning efficiency, bandwidth, and noise performance.
• Perform corner, statistical Monte Carlo, and margin analyses to establish tolerances, yield estimates, and test-vehicle inputs.
• Validate and iterate models based on empirical measurements; automate simulation and review processes.

Requirements

Must-have technical skills, tools, and behaviors required for the role. Preferred items are noted separately.

• Deep knowledge of silicon photonic device physics and analog circuit fundamentals; experience producing behavioral component models for circuit-level co-simulation.
• Practical experience with photonic simulation tools (for example Lumerical, RSoft, Tidy3D) and analog IC suites (for example Cadence Virtuoso/Spectre).
• Strong Python skills for modeling, data extraction, automation, and maintaining shared engineering codebases.
• Experience extracting/calibrating parameters using optical solvers, PDKs, and physical measurement data; ability to correlate models to silicon.
• Analytical, methodical engineering approach with emphasis on structured reviews and simulation automation.
• Clear written and verbal technical communication skills; ability to present results to cross-functional teams.
• Ability to comply with U.S. export control laws and related compliance requirements.
• Preferred: experience with microring modulators/filters, DWDM MUX/DEMUX, thermal tuning; laser and III-V photonics (DFB, external-cavity, comb sources, SOAs, wavelength lockers); analog front-end design (TIAs, modulator drivers, heater drivers, DACs); foundry silicon photonics PDKs and process-variation data; lab measurement correlation (OSA, tunable lasers, OVA/LCA, VNA, wafer-level testing); publications or patents in photonic circuit design or modeling.

Education Requirements

Ph.D. in Electrical Engineering, Applied Physics, Photonics, or a closely related field is preferred and commonly expected for senior/staff roles; the posting also indicates an M.S. is acceptable with more industry experience. Specifically, the source lists Ph.D. plus industry experience as the baseline and provides alternative experience mappings (e.g., M.S. with additional years). Equivalent practical industry experience may be considered in place of formal degrees where noted.

About the Company

Company: Lightmatter

Headquarters: Boston, Massachusetts, USA

Lightmatter develops photonic AI data-center infrastructure and optical chips for extreme-scale AI and HPC. The company invented the Passage 3D‑stacked photonics engine to provide high-bandwidth, low-latency interconnects across large-scale processors and raised $400M in Series D financing at a reported $4.4B valuation.