CROQUET

The project has the objective of creating suitable molecular entities, by exploiting coordination chemistry, for implementing quantum error correction schemes both in the bulk phase and on thick (500 nm) and thin (50 nm) films of molecules. We employ Lanthanide-Transition Metal (Ln-TM) dimers spin structures accommodating one lanthanide and one transition metal ion, which can both act as multi-level quantum objects, i.e. qudits. The chosen systems have high chemical stability, and a remarkable chemical tunability, being able to accommodate a large array of metal ions, reflected in a fine tuning and control of all the relevant spin interactions within each ion and between ions; moreover, one or both can have magnetic properties, and this permits many possible quantum computing configurations and to switch on and off, or modulate, physical parameters at will. We further propose to deposit these structures on surfaces to go towards their integration into chip-like processors and nanodevices. Of course, the surface modification constitutes another degree of freedom that we aim to exploit in this study. Our Ln-TM dimers spin structures should allow the implementation of two-qudit logic gates, where qudits are able to also sustain quantum error correction schemes.

A. Chiesa, "Molecular nanomagnets and chiral-induced spin selectivity: two useful tools for quantum technologies", invited talk at the APS Joint March Meeting and April Meeting Global Physics Summit, Anaheim (California, USA) March 16-21, 2025.

L. Bersani, "Nuclear spin qudits for the implementation of quantum algorithms with unconventional NMR techniques", oral contribution at the FisMat2025 Conference, Venice (Italy) July 7-11, 2025.

A. Chiesa, "Molecular spins: a qudit-based platform for fault-tolerant quantum computing”, oral contribution at the International Workshop "Beyond Qubit : quantum information processing with qudits", Trento (Italy) July 7-10, 2025.

E. Garlatti, "Nuclear Spin Qudits for Quantum Algorithms", invited talk at the Workshop "SELDoM2025 - Surface and electronic properties of Low Dimensional Materials", Naples (Italy), October 13-15 2025.