Cryogenic Electrical Interconnect Engineer

About this role

PsiQuantum's mission is to build the first useful quantum computers: machines capable of delivering the breakthroughs the field has long promised. Since our founding in 2016, our singular focus has been to build and deploy million-qubit, fault-tolerant quantum systems.

Quantum computers harness the laws of quantum mechanics to solve problems that even the most advanced supercomputers or AI systems will never reach. Their impact will span energy, pharmaceuticals, finance, agriculture, transportation, materials, and other foundational industries.

Our architecture and approach is based on silicon photonics. By leveraging the advanced semiconductor manufacturing industry, including partners like GlobalFoundries, we use the same high-volume processes that already produce billions of chips for telecom and consumer electronics. Photonics offers natural advantages for scale: photons don't feel heat, are immune to electromagnetic interference, and integrate with existing cryogenic cooling and standard fiber-optic infrastructure.

That approach has since been tested at the highest level of scrutiny the U.S. government applies to emerging technology, and it has held up. In 2025, PsiQuantum closed a $1 billion funding round that valued the company at $7 billion. In 2026, the U.S. Department of Commerce signed a $100 million Letter of Intent under the CHIPS and Science Act, followed by a $125 million agreement with DARPA under Stage C of its Quantum Benchmarking Initiative, PsiQuantum's most valuable U.S. government agreement to date. This year, we also broke ground on our utility-scale quantum computer in Brisbane, Australia, and continued building out our Chicago site. Victor Peng, our CEO, and co-founder Jeremy O'Brien, now Executive Chairman, lead a team and board that reflects how seriously the world is taking this build, joined this year by Intel's Lip-Bu Tan and Atomico's Niklas Zennström.

PsiQuantum also develops the algorithms and software needed to make these systems commercially valuable. Our application, software, and industry teams work directly with leading Fortune 500 companies, including Airbus, Lockheed Martin, Mercedes-Benz, Boehringer Ingelheim, and Mitsubishi Chemical, to prepare quantum solutions for real-world impact.

Quantum computing is not an extension of classical computing. It represents a fundamental shift, and a path to mastering challenges that cannot be solved any other way. The potential is enormous, and we now have the funding, the government validation, and the sites under construction to make it real.

Job Summary:

The Cryogenic Electrical Interconnect Engineer is responsible for the design, development, integration, and testing of electrical interconnect solutions used within PsiQuantum's cryogenic systems.

This role focuses on cables, connectors, electrical feedthroughs, and PCB interconnects operating in vacuum and cryogenic environments. The engineer develops the electrical connection architecture required to interconnect components within the cryostat, provide reliable connections at cryogenic temperatures, and route electrical signals through the cryostat vacuum boundary to external equipment.

The Cryogenic Electrical Interconnect Engineer combines electrical and mechanical engineering expertise to develop interconnect solutions that meet electrical performance, thermal, mechanical, vacuum, and integration requirements. The role supports engineering activities from concept development through detailed design, component selection, qualification testing, manufacturing, installation, and troubleshooting.

The ideal candidate combines electrical interconnect expertise with strong mechanical engineering judgment and an understanding of the challenges associated with vacuum and cryogenic environments.

They are comfortable working at the interface between electrical, mechanical, thermal, and cryogenic engineering and can translate electrical connectivity requirements into practical cable, connector, feedthrough, and PCB interconnect solutions.

They are able to move between detailed 3D design, component selection, engineering analysis, supplier coordination, hands-on testing, integration, and troubleshooting. Success in this role requires attention to detail, practical engineering judgment, and effective collaboration across electrical, mechanical, cryogenic, system, and supplier teams.

Responsibilities:

• Design electrical cables and cable assemblies for operation in vacuum and cryogenic environments.

• Design electrical feedthroughs and interconnect solutions across cryostat vacuum boundaries.

• Design and integrate electrical connectors for PCB and electronic components operating at cryogenic temperatures.

• Develop interconnect architectures between electronic components located inside the cryostat and external room-temperature equipment.

• Select cables, conductors, connectors, feedthroughs, insulation materials, and associated components based on electrical, thermal, mechanical, vacuum, and cryogenic requirements.

• Evaluate thermal conduction through electrical cables and interconnects and contribute to the management of cryostat thermal loads.

• Design cable routing, mechanical supports, strain relief, and thermal anchoring solutions within the cryostat.

• Evaluate mechanical and thermal effects on connectors and cable assemblies, including differential thermal contraction during cooldown and warmup.

• Develop 3D CAD models, drawings, interface definitions, and specifications for cables, connectors, feedthroughs, and associated mechanical components.

• Work closely with electrical, mechanical, PCB, cryogenic, and system engineering teams to define and manage interconnect requirements and interfaces.

• Support component selection and qualification through engineering analysis and testing.

• Develop and execute test plans to validate electrical, mechanical, thermal, vacuum, and cryogenic performance of interconnect components and…