Photonics Design Engineer

About Us

Great Sky is a technology startup based with a mission to rebuild AI from first principles. We are pursuing neuroscience-inspired hardware and algorithms that overcome the greatest challenges in scaling AI systems.
We are seeking a highly motivated PIC Design Engineer to design the detector-integrated photonic networks central to our cryogenic technology platform.
You will own the design of our active and passive photonic components and circuits, from simulation and layout through tapeout at major semiconductor foundries. You will also work with foundry process teams to make sure the designs are manufacturable.
This is a high-ownership position with substantial influence on the pace and direction of our hardware development.

How You’ll Make An Impact

• Design, simulate, and optimize passive photonic components on silicon nitride (SiN) and silicon platforms. Examples include waveguides, grating and edge couplers, splitters, mode converters, resonators, and optical I/O.
• Design active components for cryogenic operation, including waveguide-integrated superconducting nanowire single-photon detectors (SNSPDs) and phase shifters or modulators.
• Design and lay out detector-integrated photonic circuits that combine passive optical routing with integrated detectors and their electrical readout.
• Prepare tapeouts for foundry multi-project wafer (MPW) and dedicated runs, including layout, verification, design reviews against foundry PDKs, and test structures to measure component performance and process variation.
• Build and maintain our internal PDK, component libraries, and script-based layout and DRC flows (e.g., GDSFactory, KLayout), working with foundry process teams to keep them in line with process capabilities and design rules.
• Work closely with test, packaging, and systems integration teams to compare measured cryogenic performance with simulation, speeding up our design-build-test-learn cycles.

What You Bring

Required

• BS, MS or PhD in physics, electrical engineering, optics, or a related field; or equivalent practical experience.
• Strong proficiency in industry-standard electromagnetic simulation methods (FDTD/ EME) and softwares (e.g., Ansys Lumerical, Tidy3D).
• Experience designing devices on silicon nitride and/or silicon photonics platforms, such as grating couplers, edge couplers, splitters, and waveguide transitions.
• Solid understanding of photonic layout concepts, Design Rule Checking (DRC), and familiarity with standard layout tools (e.g., KLayout, Luceda, Cadence).
• Experience developing or extending a PDK, including PCells, component libraries, design rules, or compact models.

Preferred

• Experience taping out photonic designs through a foundry or MPW program (e.g., imec, AIM Photonics, Ligentec).
• Experience designing SNSPDs or other waveguide-integrated detectors, or active devices such as phase shifters and modulators.
• Experience with multi-layer SiN platforms and interlayer couplers.
• Hands-on optical and electro-optical characterization (e.g., fiber coupling, waveguide loss, grating coupler, and photodetector measurements).
• Experience with fabricating devices on at least one of these platforms: silicon photonics, silicon nitride, and/or superconducting electronics.
• Experience using AI tools, including agentic AI, to improve photonic designs and write layout code.

Benefits and Perks

• Meaningful equity ownership in an early-stage deep tech company
• Employer-matched 401(k)
• Health, dental, vision, and life insurance
• Flexible PTO — Support for ongoing learning, conference attendance, and skill development
• Our culture is onsite by default (we're founded by scientists who are used to working in the lab), with flexibility for hybrid arrangements. For the right person and role, we're open to filling roles remotely