doi:10.1103/PhysRevApplied.19.064060engChiesa, A.Roca, S.Chicco, S.de Ory, M.C.Gómez-León, A.Gomez, A.Zueco, D.Luis, F.Carretta, S.Blueprint for a molecular-spin quantum processorART-2023-134644The implementation of a universal quantum processor still poses fundamental issues related to error mitigation and correction, which demand investigation of also platforms and computing schemes alternative to the main stream. A possibility is offered by employing multilevel logical units (qudits), naturally provided by molecular spins. Here we present the blueprint of a molecular spin quantum processor consisting of single molecular nanomagnets, acting as qudits, placed within superconducting resonators adapted to the size and interactions of these molecules to achieve a strong single spin-to-photon coupling. We show how to implement a universal set of gates in such a platform and to readout the final qudit state. Single-qudit unitaries (potentially embedding multiple qubits) are implemented by fast classical drives, while an alternative scheme is introduced to obtain two-qubit gates via resonant photon exchange. The latter is compared to the dispersive approach, finding in general a significant improvement. The performance of the platform is assessed by realistic numerical simulations of gate sequences, such as Deutsch-Josza and quantum simulation algorithms. The very good results demonstrate the feasibility of the molecular route towards a universal quantum processor.2023http://zaguan.unizar.es/record/12767010.1103/PhysRevApplied.19.064060http://zaguan.unizar.es/record/127670oai:zaguan.unizar.es:127670info:eu-repo/grantAgreement/ES/DGA/E09-17R-Q-MADinfo:eu-repo/grantAgreement/EC/H2020/862893/EU/Molecular spin qudits offering new hope for quantum computing/FATMOLSThis project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No H2020 862893-FATMOLSinfo:eu-repo/grantAgreement/ES/MICINN-AEI/PID2020-115221GB-C41info:eu-repo/grantAgreement/EUR/MICINN/TED2021-131447B-C21info:eu-repo/grantAgreement/EUR/MICINN/TED2021-131447B-C22Physical Review Applied 19, 6 (2023), 064060 [17 pp.]All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess