Senior Photonics Design, Layout & Modeling Engineer

Infleqtion•Louisville, CO

16h

About The Position

Infleqtion is commercializing quantum technology, building deployable systems where photonics is the engine for performance, scale, and reliability. Our photonics team develops integrated photonics (PICs) and related optical subsystems that enable chip-scale laser sources, modulation, routing, and control for next-generation quantum products. We work closely with quantum system teams, and external foundry/assembly partners to turn ambitious optical performance targets into manufacturable hardware. Infleqtion is seeking a Senior Photonics Design, Layout & Modeling Engineer to design and deliver next-generation photonic integrated circuits and photonic subassemblies, with an emphasis on simulation-driven design, layout/verification, and rapid experimental feedback. In this role, you will own portions of PIC design from concept through tapeout and test—translating system requirements into photonic building blocks (passives, couplers, resonators, filters, modulators, etc.), performing rigorous EM/photonic modeling, completing layout and verification, and partnering with the lab team to characterize devices and iterate quickly. We are looking for a highly motivated individual who thrives in ambiguity, enjoys working in a small, dynamic team environment, and has a passion for solving hard problems that lead to high-impact technological advances.

Requirements

M.S. or Ph.D. in Electrical Engineering, Applied Physics, Photonics, or a related field (or equivalent practical experience).
[4]+ years of relevant experience designing integrated photonics (Si, SiN, InP, or related platforms) with demonstrated taped-out designs or comparable project outcomes.
Advanced proficiency in photonics simulation and modeling (e.g., EME, FDTD, FEM, BPM, eigenmode, circuit-level/Interconnect modeling) and comfort validating models against measurement.
Hands-on experience with photonic layout and verification (PDK usage, hierarchy management, mask/tapeout deliverables).
Proficiency with Python for design automation, analysis, and workflow tooling; comfort working with version control (Git).
Practical experimental familiarity: common optical test equipment and techniques (fiber coupling/alignment, insertion loss, spectrum analysis, polarization handling, interferometric/phase-sensitive measurements, basic RF/optical modulation measurements).
This position involves access to export-controlled information and/or technology. To comply with U.S. Export Control laws and regulations, candidates must be a U.S. Person (U.S. citizen, U.S. lawful permanent resident).

Nice To Haves

Multiple tapeouts at commercial foundries, including direct foundry interface and post-silicon debug.
Experience with common photonics toolchains (e.g., Lumerical, Synopsys, COMSOL) and layout stacks (e.g., KLayout, gdsfactory).
Experience designing PIC-based laser subsystems (hybrid/heterogeneous gain integration), micro-combs, narrow-linewidth sources, or frequency control photonics.
Familiarity with photonic packaging constraints (edge/vertical coupling, alignment tolerances, thermal effects) and how they feed back into PIC design.
Strong communication and presentation skills; ability to work effectively with external partners (foundries, packaging, vendors).

Responsibilities

Own and deliver high-performance photonic component designs and PIC layouts that meet aggressive specs (loss, bandwidth, phase stability, power handling, crosstalk, yield).
Build simulation-to-layout workflows that accelerate design cycles (PDK integration, reusable parameterized cells, verification automation).
Drive tapeout readiness: coordination, foundry alignment, mask submission deliverables, and post-tapeout debug loops.
Close the loop with the lab: define test plans, review data, troubleshoot discrepancies, and translate measurements into actionable design improvements.
Collaborate across teams to ensure PIC-level design choices support system-level performance, reliability, and manufacturability.