Quantum Sensing
Quantum sensors, in which the influence of external parameters on quantum superposition states is detected, have the potential to reach ultra-low sensitivities. Solid-state magnetometers based on ensembles of NV centres spins in diamond are among the most developed quantum sensors, with the first integrated devices being expected to become commercially available within the next ten years. They enable the detection of sub-picoTesla magnetic fields with high dynamic range and bandwidth, and could find applications in the fields of automotive, space, failure analysis or magnetic field sensing in biological environment.
The QST division at Imo-Imomec works on the development of photoelectrically readout NV diamond sensors, for magnetic field sensing and microwave detection. Compared to optically readout systems, these sensors could present improved sensitivities and higher compactness, as well as an easier integration with electronics. One of our objectives is the development of architectures and protocols enabling the parallel addressing of adjacent micrometric pixels, to form spatially-resolved photoelectric quantum sensors. In parallel, we develop fully integrated compact magnetometers, containing all required components, from the control and readout system to magnetic, microwave, radio-frequency, and optical manipulation tools. This type of miniaturized device is of a high interest for scientific space missions, Earth magnetic field measurements for geological exploration, satellite navigations or monitoring of space weather.
Our research aims in particular at improving the sensitivity of photoelectrically readout diamond quantum sensors, by maximizing the NV centres charge state purity and the spin initialization fidelity, minimizing the background photocurrent and improving the charge carriers collection efficiency. Achieving these goals requires to better control the NV centres environment, to improve the diamond-electrode interface and to optimize experimental parameters. Protocols are also developed to make the photoelectric readout compatible with high-frequency AC quantum sensing.
In parallel, we investigate the use of nanodiamonds containing color centres for nanoscale temperature sensing in biological environment.