Lead Photonics Design Engineer - III/V Components

About us Salience Labs is developing optical circuit switching technology for AI infrastructure, aimed at reducing latency and cost in data centre networks. As we move towards deployment, you'll have real ownership of your area and work alongside a highly technical team on a hard problem in AI infrastructure. The role You'll join a multi-disciplinary research team in the UK to lead the development of III-V active components for integration with silicon photonics. You will take devices from epitaxial stack and device design through fabrication with external partners, to characterisation, reliability and qualification. What you'll be doing - Lead the design and modelling of III-V active devices, including epitaxial layer structure, gain and power modelling, optical mode design, and electrical and thermal design - Own the technology roadmap and device specifications for your area, translating system requirements into device design and integration targets - Lead mask design and tape-outs, including GDS layouts, test structures and design-of-experiment splits - Manage fabrication runs with external epitaxy and foundry partners: define process flows, review process and in-line data, and resolve yield issues as the technology scales - Define and lead the characterisation strategy at wafer, chip and integrated-PIC level, including building and automating test setups - Analyse test data, correlate measured performance with design and process variations, and drive design iterations to close performance gaps - Work with packaging and reliability engineers on burn-in, accelerated ageing, failure analysis and qualification - Mentor engineers and, as the team grows, help recruit and develop new team members Essential requirements - PhD in physics, photonics, electrical engineering, optical engineering or a related subject with 6+ years' relevant experience, or a Master's degree with 8+ years' relevant experience, including at least 4 years' hands-on development of III-V optical amplifiers or semiconductor lasers, preferably in industry - Proven track record of taking III-V devices from concept through design, fabrication and test, ideally including qualification - Deep understanding of semiconductor laser and amplifier physics: optical gain, carrier dynamics, quantum-well design, noise, gain saturation and nonlinearities, thermal effects and polarisation dependence - Hands-on knowledge of III-V epitaxy and fabrication processes (e.g. MOCVD/MBE growth, lithography, etching, passivation, metallisation, facet/AR coating), and experience working with external foundries - Experience characterising amplifiers or lasers, including optical spectrum analysis, gain and noise measurement, wafer-level probing, temperature-controlled testing and test automation - Experience with simulation and layout tools for photonic devices, such as Lumerical, Photon Design, Crosslight, RSoft, COMSOL, KLayout, L-Edit or Cadence Virtuoso - Proven ability to lead technical projects across design, process, test and packaging functions, and experience mentoring or supervising engineers - Excellent communication skills, critical thinking, attention to detail and self-motivation Nice to have - Experience integrating III-V active devices with silicon photonics, including coupling design between III-V and silicon waveguides - Experience line-managing a technical team - Experience with reliability testing and failure analysis of III-V devices - Experience developing PDK building blocks or compact models for active devices - Programming experience (Python, MATLAB or C++) for simulation, test automation and data analysis - Knowledge of photonic packaging, including fibre coupling, thermal design and TEC control - A track record of high-quality patents and research papers