On-chip magnetic resonance

Building a hybrid QPU involves the development of methods and devices that optimize the coupling of spins to photons trapped in superconducting cavities.

This coupling forms the basis of magnetic resonance, a technique of widespread use for research in Physics, Chemistry and Material Science, but also a very powerful analytical tool in Biology, Medicine, and the detection of contaminant.

We aim to take this technique into a new level in terms of sensitivity, also expanding its operation range to very low temperatures and frequencies between 400 MHz and 14 GHz, thus covering typical NMR and EPR bands.

We apply ion-beam lithography to fabricate LC resonators able to confine the photon magnetic fields into regions with lateral dimensions as small as 40-50 nm.

Molecular spins and magnetic nanostructures are delivered into these regions by means of an atomic force microscope or by other nano-positioning tools. This has led to the achievement of record spin-photon interactions and to magnetic resonance experiments on pico-liter samples. Our next goals are: 1) expand this technique with pulse EPR methods to explore the coherent dynamics of spin qubits and of topological excitations in magnetic nanostructures, 2) perform magnetic resonance on biological nano-materials.

Last but not least, we plan to exploit electronic spins as local quantum sensors to measure nuclear magnetic resonance at the level of individual cells.