Senior Scientist - Cryogenic Detector Metrology (Hybrid)

About Xanadu

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!

Your Role And Responsibilities

As a Senior Scientist specializing in cryogenic detector metrology, you will contribute your expertise in cryogenics and precision measurement to further the performance and scalability of our transition edge sensor (TES) platform. As part of the Low Temperature Devices team, you will take ownership of the development, implementation, and deployment of an ultra-high-accuracy system detection efficiency (SDE) metrology capability for our TES-based photon-number-resolving detectors.

You will be responsible for designing and validating a near-infrared metrology system that sets new standards in stability, repeatability, and accuracy. This includes full system optimization including component selection, control, monitoring, data analysis and integration within our cryogenic detector infrastructure.

Responsibilities

This role demands deep experience with milli-Kelvin cryogenic systems, exceptional attention to detail, and a strong foundation in detector physics and optical metrology. You will ensure that our SDE measurements are not only accurate, but scalable and production-ready. Responsibilities include:

• Lead the implementation of an ultra-high-accuracy metrology system for measuring TES system detection efficiency at near-infrared wavelengths
• Independently operate and maintain milli-Kelvin cryostats (dilution refrigerators).
• Integrate and operate a cryogenic radiometer as an optical power reference standard
• Perform detailed cryostat-based TES characterization to validate performance, repeatability, and long-term stability of SDE measurements
• Identify and resolve subtle system-level effects that influence detection efficiency, such as thermal drifts, and background noise suppression
• Prototype and optimize precision optical layouts, mounts, and calibration methods suitable for cryogenic environments
• Define measurement protocols and statistical analysis pipelines to support rigorous validation of large-scale detector array performance
• Interface with internal teams and external collaborators
• Contribute to pushing the state-of-the-art in precision measurement for single-photon detectors
  
  

Basic Qualifications And Experience

• PhD in Physics, Electrical/Mechanical Engineering, or a related field, with at least 2 years of postdoctoral or industry experience
• Extensive hands-on experience with milli-Kelvin cryostats (preferably dilution refrigerators), including cooldown, troubleshooting, and maintenance
• Proven track record in high-precision measurement, metrology, or detector calibration
• Familiarity with TES, MKID, SNSPD, or other cryogenic detector technologies
• Extreme attention to detail and a systematic approach to experimentation, with a focus on minimizing both systematic and statistical errors — essential qualities for high-precision metrology.
• Experience with analog test equipment (e.g., SMU, VNA, photodetectors)
• Excellent interpersonal and written communication skills
• Comfortable working both independently and collaboratively on multidisciplinary hardware projects in a dynamic environment
  
  

Preferred Qualifications And Experience

• Experience with Python-based lab automation or data acquisition
• CAD and simulation experience for optical, thermal, or mechanical design (e.g., SolidWorks, COMSOL, Zemax)
• Familiarity with fiber-coupled optical systems
  
  

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At Xanadu, 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 [email protected].

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