Designed polynuclear lanthanide complexes for quantum information processing

The design of dissymmetric organic ligands featuring combinations of 1,3-diketone and 2,6-diacetylpyridine coordination pockets has been exploited to produce dinuclear and trinuclear lanthanide-based coordination compounds. These molecules exhibit two or more non-equivalent Ln ions, most remarkably enabling the access to well-defined heterolanthanide compositions. The site-selective disposition of each metal ion within the molecular entities allows the study of each centre individually as a spin-based quantum bit, affording unparalleled versatility for quantum gate design. The inherent weak interaction between the Ln ions permits the performance of multi-qubit quantum logical operations realized through their derived magnetic states, or implementing quantum-error correction protocols. The different studies performed to date on these systems are revised, showing their vast potential within spin-based quantum information processing.The authors thank the European Union's Horizon 2020 research and innovation programmes, the QUANTERA project SUMO, the FET-OPEN FATMOLS (grant 862893; GA and OR), the Spanish MICINN (grants PGC2018-098630-B-I00 (GA and DA) and MAT2017-86826-R (OR)) and the Generalitat de Catalunya for the ICREA Academia 2018 Prize (GA)