Senior Mechanical Design Engineer

PsiQuantum•Milpitas, CA

About The Position

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. In 2024, PsiQuantum announced government-funded projects to support the build-out of our first utility-scale quantum computers in Brisbane, Australia, and Chicago, Illinois. These initiatives reflect a growing recognition that quantum computing will be strategically and economically defining—and that now is the time to scale. 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 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 have a clear path to make it real. Come join us. Job Summary: The Senior Mechanical Design Engineer is responsible for designing and qualifying the performance of innovative electro-optical subsystems, working closely with electronics packaging, systems integration and edge coupling teams.

Requirements

Master’s Degree in Mechanical Engineering or a relevant discipline.
Minimum 5 years of experience; Preferred – 10 years of experience.
Working knowledge of DfM and design issues associated with volume production, ideally with direct experience.

Responsibilities

Ability to work independently with limited direction, in a team environment across functional and organizational boundaries is required.
Assist with systems architecture development at the sub-system level.
Perform large or complex portions of projects where responsibility includes definition, completion, technical quality, across teams.
Provides frequent written and oral presentations, status reports, and updates, for a variety of audiences.
Ability to accept constructive feedback from resident experts and coordinate communications between different groups.
Serve as mentor to younger engineers.
Ability to distill complex mechanical issues and drive convergence amongst electrical, optical & packaging teams.
Mechanical design work, including:
Strong mechanical design and analysis skills, expertise in GD&T
Generate & maintain BOM’s & build standards
Generate and maintain process flow documentation
Integration of CAD files across multiple teams
Fixture design & fabrication
Test set-up design & fabrication
Generating & maintaining a Specification Tree
Generating & maintaining a Drawing Tree for builds & variants
Management of builds through the use of PDM / Arena
Tolerance analysis – RSS & worst case
DFMEA & risk analysis heat maps
Input & maintain workflow documentation in MES
Perform simple simulations of structural deflections, stresses