Your role at C12 Quantum Electronics:
- You will design RF and microwave architectures for quantum control, readout, amplification, and signal routing.
- You will develop components and subsystems including filters, amplifiers, mixers, couplers, resonators, attenuators, bias networks, and impedance-matching structures.
- You will design and validate room-temperature and cryogenic RF signal chains.
- You will perform electromagnetic simulation, link-budget analysis, noise analysis, and signal-integrity optimization.
- You will characterize components and systems using vector network analyzers, spectrum analyzers, signal generators, oscilloscopes, and noise-measurement equipment.
- You will optimize phase noise, noise figure, gain, linearity, isolation, bandwidth, cross-talk, and thermal loading.
- You will develop calibration, de-embedding, and automated test procedures.
- You will support the integration of RF electronics with quantum processors, cryostats, interposers, PCBs, cables, connectors, and advanced packaging.
- You will diagnose performance limitations involving reflections, interference, grounding, shielding, drift, and thermal effects.
- You will define requirements, interfaces, test plans, and acceptance criteria for RF subsystems.
- You will lead technical reviews and collaborate with quantum scientists, electronics engineers, packaging teams, firmware developers, and external suppliers.
- You will mentor junior engineers and contribute to RF design standards, technology roadmaps, and laboratory best practices.
We are seeking a Senior Quantum RF Engineer to lead the design, integration, and validation of RF and microwave systems for quantum-computing hardware.
You will develop low-noise, high-fidelity signal chains supporting quantum-device control and readout, from room-temperature electronics through cryogenic interconnects and device packaging.
About you:
- Master’s degree or PhD in electrical engineering, applied physics, quantum engineering, or a related field.
- You have substantial experience designing and testing RF or microwave systems.
- You have strong knowledge of S-parameters, impedance matching, transmission lines, resonators, noise, nonlinearities, and signal integrity.
- You have experience with electromagnetic and circuit-simulation tools such as Ansys HFSS, CST Studio Suite, Keysight ADS, or equivalent.
- You have hands-on experience with RF laboratory instrumentation and measurement techniques.
- You have experience designing RF PCBs, microwave assemblies, or integrated interconnects.
- You have proficiency with Python, MATLAB, or similar tools for automation and data analysis.
- You have demonstrated ability to lead complex technical projects and resolve multidisciplinary engineering problems.
- Experience with superconducting, semiconductor-spin, trapped-ion, neutral-atom, or other quantum-computing platforms.
- Knowledge of qubit control and dispersive readout techniques.
- Experience developing systems operating at cryogenic temperatures.
- Familiarity with cryogenic amplifiers, circulators, isolators, parametric amplifiers, and superconducting microwave devices.
- Experience with IQ modulation, direct digital synthesis, FPGA-based control, multiplexed readout, or real-time feedback.
- Understanding of electromagnetic compatibility, packaging effects, thermalization, and magnetic shielding.
- Experience transitioning RF systems from laboratory prototypes to reliable, scalable products.
- Record of technical leadership, patents, publications, or contributions to complex research programs.
What we offer:
- 66,000 euros - 78,000 euros yearly base salary
- Stock options for every employee (BSPCE/ESOP)
- Sponsored trip to conferences around the world
- A highly dynamic international team
- Swile meal vouchers
- Mental health support with moka.care
- Training budget/ Annual Learning & Development Allowance
- Sabbatical leave (after 2 years in the company)
- Vibrant office culture (two office spaces in the heart of Paris, team lunches, offsite events, Friday breakfasts..)
What we offer:
You should join us if...
- You want to have a key role in a growing startup with challenges at the frontier of the technology.
- You want to contribute to achieving landmark results in quantum computing, making a difference in the emerging quantum technologies.
- You want to work within a 60-people team with various backgrounds in nanofabrication, quantum electronics, and carbon nanotube science to create a revolutionary quantum computing processor.
- You want to thrive in an exceptional scientific environment with several industrial and academic partners.
- You share our values (excellence, scientific integrity, diversity, curiosity, and care) and want to help us define our product-focused culture and ambition to accelerate.
Skills Required
- Master's degree or PhD in electrical engineering, applied physics, quantum engineering, or related field
- Substantial experience designing and testing RF or microwave systems
- Strong knowledge of S-parameters, impedance matching, transmission lines, resonators, noise, nonlinearities, and signal integrity
- Experience with electromagnetic and circuit-simulation tools (Ansys HFSS, CST Studio Suite, Keysight ADS or equivalent)
- Hands-on experience with RF laboratory instrumentation and measurement techniques (VNAs, spectrum analyzers, signal generators, oscilloscopes, noise measurement)
- Experience designing RF PCBs, microwave assemblies, or integrated interconnects
- Proficiency with Python, MATLAB, or similar tools for automation and data analysis
- Demonstrated ability to lead complex technical projects and resolve multidisciplinary engineering problems
- Experience with superconducting, semiconductor-spin, trapped-ion, neutral-atom, or other quantum-computing platforms
- Knowledge of qubit control and dispersive readout techniques
- Experience developing systems operating at cryogenic temperatures
- Familiarity with cryogenic amplifiers, circulators, isolators, parametric amplifiers, and superconducting microwave devices
- Experience with IQ modulation, direct digital synthesis, and FPGA-based control
- Understanding of electromagnetic compatibility, packaging effects, thermalization, and magnetic shielding
- Experience transitioning RF systems from laboratory prototypes to reliable, scalable products
- Record of technical leadership, patents, publications, or contributions to complex research programs
What We Do
C12 is building reliable quantum computers. The company is a spin-off from ENS launched in January 2020 by twin brothers Matthieu and Pierre Desjardins to supercharge the development of the lab’s promising new quantum technology. Quantum computing has the potential to change our lives. But frequent errors limit the technology’s viability. We are tackling the fundamental issue: the nature of the hardware itself. We are tapping into the simplest material–carbon–to drive a technological breakthrough in the field. Unlike other quantum computers, we use carbon nanotubes as the fundamental building block of our processor. By combining the power of an ultra-pure material with an easy-to-manufacture semiconductor device, we are building a scalable platform for quantum computing. Our executive co-founders bring a unique combination of scientific excellence and business skills to the company. Our team is made up of the world’s most accomplished experts in quantum electronics and carbon nanotube science. Our scientific advisors are renowned scientists and pioneers in spin qubits: Dr. Takis Kontos, Dr. Matthieu Delbecq and Dr. Jérémie Viennot. In June 2021, C12 secured a $10 million seed round with funding from 360 Capital, Bpifrance (Digital Venture Fund), Airbus Ventures, BNP Paribas Développement, and Octave Klaba (OVHcloud), and additional grants from Bpifrance and the Ile-de-France Region. We are leading quantum’s next material breakthrough, and we are just getting started. Silicon enabled the emergence of classical computing – it’s time for carbon to do the same for quantum !
