Senior Low Temperature Device Engineer in Toronto

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. 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!

Your role and responsibilities:

• Apply your expertise in superconducting single-photon detector engineering to advance the performance and scalability of our SNSPD platform.
• Design high-performance single-photon detectors with ultra-high system detection efficiency, fast reset times, and scalable integration into large detector arrays.
• Work across design, simulation, layout, and testing to take devices from concept through validation and deployment.
• Drive improvements in key SNSPD performance metrics relevant to Xanadu’s architecture through device design and optimization.
• Translate device designs into tapeout-ready GDS layouts for fabrication with external foundries.
• Contribute to the end-to-end device development lifecycle, from concept through validation and deployment in multi-pixel arrays.
• Develop and execute cryogenic test plans to characterize detector performance.
• Execute iterative cryogenic testing to validate optical coupling, performance repeatability, and long-term stability.
• Analyze device performance data to inform design iterations and process improvements.
• Collaborate with internal teams and external partners across process integration, packaging, and fabrication.
• Contribute to scaling strategies for high-density detector arrays, including layout, integration, and multiplexing constraints.

Basic qualifications and experience:

• PhD in Physics, Electrical Engineering, Mechanical Engineering, or a closely related field, plus at least 2 years of postdoctoral or industry experience.
• Demonstrated experience designing, laying out, and characterizing SNSPDs.
• Strong understanding of superconducting device physics and single-photon detection mechanisms.
• Hands-on experience with cryogenic measurement systems and device characterization.
• Experience using analog test equipment (e.g., VNA, SMU) for high-frequency and low-noise measurements.
• Experience using Python for component design, simulation, layout, and data analysis.
• Ability to work independently and collaboratively in a fast-paced, cross-disciplinary environment.
• Strong attention to detail and a rigorous, data-driven approach to problem solving.
• Excellent written and verbal communication skills.

Preferred qualifications and experience:

• Experience operating sub-Kelvin helium-based cryostats, including cooldown, troubleshooting, and maintenance.
• Experience with high-bandwidth RF readout and detector interfacing.
• Simulation experience for device-level modeling (e.g., COMSOL, pyTDGL).
• Familiarity with statistical process control and yield optimization in fabrication workflows.
• Experience with large-scale detector arrays or multiplexed readout architectures.

This is for a new position. Your base salary will be determined based on your location, experience, and internal benchmarks. The base salary range is 150000 - 200000 CAD. You will also be eligible for equity and benefits.

Our values are important. They are fundamental and lay the foundation for culture at Xanadu. We are an equal opportunity employer and encourage candidates of all backgrounds to apply. We are committed to building an inclusive, safe, and equitable culture and fostering an environment where our employees feel included, valued, and heard. We are committed to meeting the needs of all individuals and support a barrier-free workplace. Should you require accommodations at any point during the recruitment process please contact Recruiting at recruiting@xanadu.ai.

Please be advised that we may use artificial intelligence (AI) tools to assist in the screening and assessment of applicants for this position. These tools assist our recruitment team but do not replace human judgment. Final hiring decisions are ultimately made by humans.