Senior Photonics Application Engineer

Are you the engineer customers want on the call when they ask whether a TFLN PIC can meet their system requirements? At Lightium, we’re pioneering next-generation photonic integrated circuits (PICs) built on thin-film lithium niobate (TFLN), and we’re looking for a Senior Photonics Application Engineer to be the technical face of Lightium from a customer’s first inquiry to the day their design is onboarded and ready for tape-out. You will shape how every new customer experiences Lightium.

Position Summary

In this role, you’ll join our Commercial Team, reporting to the CRO, and own the pre-sales customer journey: first contact, technical qualification, feasibility assessment, quotation, purchase order, and onboarding. You will turn customer requirements into a credible technical scope, position the right path (MPW, dedicated lot, or production) on our mature O-band and C-band PDK, and make sure each customer starts with a design flow, design rules, and expectations that set them up to succeed. Your work is the bridge between what our customers need and what our R&D and operations teams can deliver. You know what a customer looks for in a foundry because you have been that customer: you have taken designs to tape-out on external PDKs and seen what separates a foundry you can build a product on from one you can’t.

Key Responsibilities

Pre-Sales Technical Ownership: Act as the first technical contact for inbound and outbound opportunities across telecom, datacom, quantum, defense, AI, and health, from R&D labs to OEMs and hyperscalers. Qualify requirements against our platform (modulator bandwidth, drive voltage, waveguide loss, wavelength band), assess feasibility, and tell customers early and honestly when a requirement does not fit. Own the technical side of every opportunity until the PO is signed.

Technical Scope & Quotation: Define the technical scope of each quotation together with Operations and Sales, covering process, test, known good die (KGD) requirements, and packaging options. Make sure each PO matches the quoted technical scope before it enters production.

Documentation: Record technical requirements, decisions, and customer commitments in the CRM in a form that the Sales team can pick up without asking you.

Customer Onboarding & Design Enablement: Run structured onboarding for every new customer: kick-off, PDK delivery and design-flow setup, training sessions, and regular design office hours. Review customer designs and layouts before submission, run design rule checks (DRC), and advise on optimizing performance, test structures, and compatibility with Lightium’s PDK, characterization, and packaging standards, so designs go to the fab clean the first time.

Voice of the Customer: Bring structured customer feedback into R&D and product decisions: PDK gaps, design rule questions, requested components, and packaging needs. Turn recurring questions into reusable assets (design guides, FAQs, onboarding material, webinar content) in collaboration with our Marketing & Communication Lead.

Industry & Customer Presence: Represent Lightium’s technical credibility at trade shows, conferences, and customer visits. This position requires regular international travel and some meetings outside standard European office hours to reach customers in other time zones.

What you’ll bring

Educational Background: A PhD or Master’s degree in Photonics, Electrical Engineering, Physics, or a related field.

Experience: 5+ years of industry experience in integrated photonics design, applications engineering, or a technical customer-facing role in SiPh, SiN, InP, or TFLN, with a track record of supporting external customers through design and fabrication. You know what a customer expects from a foundry: PDK quality, design rule clarity, yield transparency, test data, and turnaround. Experience in designing photonic engines at a transceiver or system level (IMDD, Coherent, or Coherent Lite) is a strong plus.

Technical Skills: Hands-on proficiency with PIC design and EDA tools (such as Luceda IPKISS, Nazca, Synopsys, or KLayout) and deep familiarity with PDKs and design rule checks (DRC, LVS, etc.). Solid understanding of electro-optic characterization and testing, and of packaging requirements. Breadth across PIC applications, from telecom and datacom to quantum and sensing.

Commercial Mindset: You are comfortable discussing scope, lead times, and price with customers, and you see a clean quote and a smooth onboarding as part of the technical job. You can say no to a poor-fit request and keep the relationship strong.

Communication: You explain complex technical trade-offs clearly to a customer’s engineering team and to their procurement or program lead, in the same week. You can compare and assess different competing technologies and platforms in customer conversations.

Ownership & Collaboration: You get things done leveraging your indirect leadership skills across R&D, Operations, and Account Management. You close loops, follow up, and do not leave open items with customers or colleagues.

Adaptability: The ability to thrive in a fast-paced startup where processes are still being built, and the drive to build them yourself.

Language Skills: Fluency in English is required. Chinese or any other Asian language is a plus.

What We Offer

A unique opportunity to build Lightium’s commercial engine from the ground up at a deep tech company with genuine technical differentiation and a clear path to high-volume production.

Competitive compensation and benefits package, including an employee stock option plan (ESOP), reflective of your experience and expertise.

Become a key player in an early-phase startup and be part of an impact-driven and diverse team. You will have the unique opportunity to create, grow, and develop your professional skills at a fast pace.

We'd love to hear from you if you're passionate about building new tech from the ground up and thrive in a collaborative and innovative environment. Lightium is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive environment for all employees.