Senior Photonics Engineer - Homodyne detection

About Xanadu:

Xanadu’s mission is to build quantum computers that are useful and available to people everywhere.

At Xanadu, we are learners, innovators, researchers, collaborators and problem solvers. We are creating something that has never been built before. What we are doing is extremely hard, the classic moon shot. Few people in their life will be able to be a part of something like this, where if we are successful, the technologies we develop will solve some of the world’s most challenging problems, and literally change the world.

And that is something to be excited about!

We are seeking a Senior Photonic Engineer – Integrated Homodyne to participate in designing, developing and experimentally validating cutting‑edge photonic systems. You will be working with photonic chips that include networks of high‑speed electro‑optic modulators and integrated balanced homodyne detectors, with a particular focus on high‑efficiency pulsed homodyne detection and pulsed quantum homodyne tomography.

• Design, build and upgrade complex optical laboratory experiments to characterize the performance of photonic integrated chips with electro‑optic elements, using continuous‑wave and pulsed laser light.
• Characterize and benchmark the performance of integrated balanced homodyne detectors for pulsed signals, with bandwidths in the hundreds of MHz regime.
• Design and build new characterization strategies as needed, to fit evolving optical/electrical requirements.
• Measure figures of merit including detection efficiency, noise clearance, effective bandwidth, common‑mode rejection, cross‑talk etc.
• Benchmark and drive further development of signal processing techniques for pulsed homodyne detection & homodyne tomography of quantum states of light.
• Maintain up‑to‑date familiarity with research trends in measuring quantum states of light.
• Implement and maintain optical phase‑locked loops and related frequency/phase stabilization; design and troubleshoot chip control electronics, PID controllers and high‑precision locking schemes for ultra‑stable electronic and optical systems; contribute to the development and assessment of new phase‑locking and calibration protocols.
• Closely collaborate with PIC development, electrical, mechanical, and software engineering teams to ensure successful module integration.
• Generate detailed technical documentation, including design specifications, test procedures, characterization reports, and operational manuals.

• Optics expertise:
  Hands‑on experimental optics lab experience, with knowledge in integrated optics & fibre optics, locking optical interferometers & noise characterization.
• Homodyne detection:
  Direct experience with homodyne detection of optical signals. Experience with pulsed homodyne detection is preferred, but not required.
• Electronics:
  Working familiarity with opto‑electronic detectors, transimpedance amplifiers; sound understanding of common RF electronics & electro‑optic modulator concepts.
• Education:
  
  Ph.D. in Quantum Optics, Photonics, AMO, Electrical Engineering or a closely related field.

• Prior work experience:
  Greater than 4 years of experience in any of: quantum computing (particularly in optical quantum computing); thin‑film lithium niobate modulators; or waveguide‑integrated photodiodes.
• Advanced quantum optics:
  Demonstrated expertise in pulsed homodyne detection and homodyne tomography of quantum optical states, alongside familiarity with recent research in these areas.
• Autonomy and technical adaptability:
  The ability to independently design, build, and troubleshoot complex optical experiments and clearly communicate measurement‑derived insights; the ability to rapidly absorb complex, proprietary architectures and master new experimental frameworks.
• Advanced Automation:
  Experience writing Python scripts for instrument control, hardware interfacing, and automated data acquisition.
• Modeling & Analysis
  
  Skills:
  
  Proven ability to build mathematical models of physical systems utilizing both analytical and numerical tools; expertise in advanced signal processing…