Lead Photonics Designer Engineer - III/V Components

About Us Salience Labs is building an industry-defining approach to optical circuit switching for AI infrastructure, engineered for real latency reduction and cost savings. We're moving towards real-world deployment, and joining at this stage means genuine ownership over that next chapter, working alongside a highly technical team on one of the most consequential problems in AI infrastructure today. The Role You will be joining a multi-disciplinary research team in the UK, working closely with other engineers, to lead the development of III-V active components – primarily semiconductor optical amplifiers (SOAs) – integrated on our silicon. As the technical owner of our SOA technology, you will take devices from epitaxial stack and device design, through fabrication with our III-V and silicon photonics foundry partners, to characterisation, reliability and qualification. What You'll Be Doing Work hands-on and lead the design and modelling of III-V SOAs and related active components, including epitaxial layer structure, gain and saturation power modelling, optical mode design, and electrical and thermal designOwn the SOA technology roadmap and device specifications, translating system requirements (gain, saturation output power, noise figure, polarization dependence, linearity and thermal budget) into device design and integration targetsLead mask design and tape-outs: generate and review GDS layouts, test structures and design-of-experiment splitsManage fabrication runs with external epitaxy, III-V and silicon photonics foundry partners: define process flows and specifications, review process and in-line data, resolve yield issues and support the transition into volume manufacturingDefine and lead the characterisation strategy for SOAs at wafer, chip and integrated-PIC level (LIV, gain and ASE spectra, noise figure, saturation output power, polarisation-dependent gain, temperature dependence), including building and automating test setupsAnalyse test data, correlate measured performance with design and process variations, identify performance gaps and drive design iterations to close themWork with packaging and reliability engineers on burn-in, accelerated ageing, failure analysis and qualification of SOA devicesMentor engineers now and, as the team grows, recruit, line-manage and develop a small team of III-V design and test engineers Essential Requirements Ph.D. 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 SOAs or semiconductor lasers, preferably in industryDemonstrated track record of taking SOAs (or semiconductor lasers) from concept through design, fabrication and test, ideally including devices taken through qualificationDeep understanding of semiconductor laser and amplifier physics: optical gain, carrier dynamics, quantum-well design, amplified spontaneous emission and noise, gain saturation and nonlinearities, thermal effects and polarisation dependenceHands-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 foundriesExperience with characterising SOAs or lasers, including optical spectrum analysers, gain and noise-figure measurement, wafer-level probing, temperature-controlled testing and test automationExperience with mainstream simulation and layout tools for active and passive photonic devices, such as Lumerical (including MQW/CHARGE/HEAT), Photon Design (PICWave, FIMMWAVE/Harold), Crosslight, RSoft, COMSOL, KLayout, L-Edit or Cadence VirtuosoProven ability to lead technical projects and coordinate across design, process, test and packaging functions, together with experience mentoring or supervising engineersExcellent communication skills, critical thinking, attention to detail and self-motivation Nice to have Experience integrating III-V active devices with silicon photonics, including mode conversion and coupling design between III-V and silicon waveguidesExperience line-managing a technical team, including recruitment and performance developmentExperience with reliability testing and failure analysis of III-V devices (e.g. accelerated ageing, catastrophic optical damage)Experience developing PDK building blocks or compact models for active devicesExperience in programming languages, such as Python, MATLAB or C++, for simulation, test automation and data analysisKnowledge of photonic packaging, including fibre coupling, thermal design and TEC controlDemonstrated ability to generate high quality patents and research papers Salience Labs Limited is a leader in photonic solutions targeting connectivity for AI datacenter infrastructure. Backed by over a decade of research from the University of Oxford in the UK and the University of Münster in Germany, Salience’s innovative developments in photonic switching technology enable high-speed, ultra-low latency networking fabrics that remove infrastructure bottlenecks for AI workloads.