Quantum Systems Engineer

About the role

Systems and Engineering builds and maintains everything a superconducting quantum processor needs in order to run: dilution refrigerators, cryogenic and room-temperature wiring, RF and DC signal chains, control electronics, racks, instrumentation, and the Python layer that drives them. We build these systems for deployment at customer sites, not only for our own lab.

You would work at system and rack level. That means selecting and integrating components into a working chain, characterizing that chain, and diagnosing it when it misbehaves. It is not component, board or chip design. Because the processor is more sensitive than any instrument in the lab, a large part of the diagnostic work is tracing an anomalous qubit measurement back to its real cause in the wiring, the grounding or the thermal path.

Within about six months you would take ownership of one setup: its wiring, its cooldowns and its numbers.

What you would do:

• Run cooldowns and warmups on dilution refrigerators, mount and change samples, and maintain vacuum, pulse tubes, compressors and helium lines, including leak checking.

• Install and thermalize coaxial and DC looms inside the fridge, and verify heat loads and thermal budgets against measured stage and qubit temperatures rather than datasheet figures.

• Build and characterize signal chains (bias tees, directional couplers, combiners, filters, HEMT and parametric amplifiers) on a network analyzer first, and then again under real pulse sequences.

• Investigate grounding and noise: measure a grounding topology before documenting it, and track down noise floors that shift when an instrument is connected.

• Integrate and validate the racks, control electronics and lab instrumentation that other teams depend on.

• Extend the Python that runs the lab: our instrument control library, the thermal calculator and the RF analysis tooling.

• Document each intervention well enough for a colleague to repeat it, and support deployments at the Barcelona Supercomputing Center, which means a few day trips a year.

We do not own qubit design, chip fabrication, quantum algorithms or the calibration libraries. Other teams here do those.

Two tracks

Everyone in the team travels and everyone debugs, but we hire into one of two focus areas:

• Electronics and instrumentation. Room-temperature RF and DC signal chains, bench characterization, grounding and noise, control electronics, racks, board and packaging support.

• Cryogenics, vacuum and thermal. Dilution refrigerators, cryogenic wiring and thermalization, heat loads and thermal budgets, vacuum and leak hunting, mechanical integration, site readiness.