Alice Castan
C12 Quantum Electronics
C12 Quantum Electronics is a spinoff of the Physics Laboratory of the Ecole Normale Supérieure (LPENS) in Paris, France. The company was founded in the beginning of 2020 with the ambitious goal to build a carbon nanotube (CNT)-based quantum processor. From a team of a few scientists at its earliest stage, C12 grew – after securing a $10M seed round in 2021 – into a multiteam organization with over 30 employees. The technology developed at C12 is based on over a decade of research led by CNRS research director Takis Kontos at the LPENS on the use of CNTs in hybrid quantum circuits.
An ultra-clean CNT is directly transferred onto a microchip, where it is suspended over a series of gate electrodes that allow the formation of a double quantum dot (DQD) in which a single electron can be trapped. The spin of the electron is then addressed through coupling to a superconducting microwave circuit. The unique possibility of selectively embedding the CNT or removing it from the microchip at the end of the chip fabrication process provides an opportunity to preselect the qubits integrated in our processor, which is absent from other spin qubit-based quantum computing technologies.
This seminar will give an overview of C12 as well as a presentation of the technology developed in its Paris-based laboratory. Focusing on the core material that makes this technology uniquely promising, we will show how the atomic structure, cleanliness, and isotopic purity of the CNTs acting as the spin qubit hosts influence the performance of the device and how measuring and controlling these parameters can help achieve record fidelity and scalability.