RF / Superconducting Device Physicist

Job Title

RF / Superconducting Device Physicist

Role Summary

Owner of end-to-end low-temperature characterization for Josephson junctions and PCL logic cells. You will design measurement protocols, extract device parameters, interpret anomalies, and produce reproducible methodology that informs process and design decisions.

Team: Superconducting Device Physics. On-site role in Snowcap labs (Jacksonville Metro, FL and San Francisco Bay Area). Base range USD 141,000–260,000.

Experience Level

Mid-level (mid-career). Advanced experimental research experience expected; specific years of experience not specified.

Responsibilities

You will lead measurement design, execution, analysis, and documentation that feed back into fabrication and circuit decisions.

• Own end-to-end characterization of Josephson junctions and PCL logic cells at cryogenic temperatures, from measurement design through interpretation.
• Design and execute custom measurement protocols to extract device parameters, including metrics without standard procedures.
• Drive process-measurement feedback with fab engineers to identify process drift, integration issues, and yield levers.
• Interpret data to inform circuit and process decisions and challenge unsupported changes.
• Produce publication-quality documentation and reproducible methodology for internal and external use.
• Improve noise floor and calibration practices for cryogenic measurement environments.
• Collaborate with device designers, process engineers, and test engineers to translate device-physics findings into engineering actions.
• Mentor junior researchers and lab staff on measurement technique, calibration, and experimental rigor.

Requirements

Key must-have skills and experience; candidates should meet most must-have items.

• Direct, hands-on characterization experience with Josephson junctions, SQUIDs, or related superconducting circuits at low temperature.
• Deep, practical knowledge of cryogenic measurement environments: noise floors, thermal anchoring, RF/microwave signal integrity through the cold chain, and calibration limits.
• Proven experimental rigor: reproducibility, uncertainty quantification, and methodology documentation used by others.
• Ability to communicate results clearly across physics and engineering audiences.
• Evidence of ownership of experimental programs (e.g., led measurement campaigns, authored methodology deliverables).

Nice-to-have:

• Postdoctoral or staff scientist experience at leading superconducting-electronics, qubit hardware, or cryogenic detector groups.
• Hands-on familiarity with superconducting thin-film platforms (NbTiN, NbN) and the device-level signatures of process variation.
• Strong Python or scientific-computing skills for automation and data-analysis pipelines.
• EM and microwave simulation experience tied to cryogenic measurement outcomes.
• Experience scaling research measurement into production-grade characterization workflows.

Education Requirements

PhD in physics, applied physics, or electrical engineering with a focus on superconducting devices, or equivalent research depth demonstrated through industry or laboratory work that led complete device measurement campaigns. Postdoctoral or equivalent advanced research experience is recognized as relevant.

About the Company

Company: Snowcap Compute

Headquarters: San Francisco, CA, United States

Snowcap Compute develops commercial superconducting digital computers using Josephson junction–based PCL logic that operate at cryogenic temperatures, aiming for dramatically lower power than CMOS. The company combines expertise in quantum physics, cryogenic engineering, and semiconductor manufacturing to build production superconducting chips.