Coherent manipulation and cavity integration of rare-earth-ion-based organic molecular systems for quantum information applications

Rare-earth-doped solid-state materials are an attractive option for the realization of quantum registers given their long coherence and compatibility with current telecommunication infrastructure. However, the low oscillator strengths present in such systems limits the ability to create efficient devices. Rare-earth-based organic molecules offer a solution to this problem through engineering the optical and spin properties with synthetic chemistry, which in turn allows for the possibility to produce multi-qubit systems within a single molecule, and self-assembly to construct large qubit registers.



We report on the characterization of multiple europium- and ytterbium-based molecular complexes. In particular, we further the work performed by on Eu(Ba)₄(pip) by measuring spin signatures and performing class preparation. Additionally, the binuclear complex [Eu(btfa)₃]₂bpm has shown a branching ratio of 1.35%, and a promising optical coherence time of 2.0 µs at 500 mK. Furthermore, the Yb(tpip)₃ complex has shown long optical lifetimes and high quantum yields.



Work is currently underway in order to integrate such complexes into a fiber-based Fabry-Pérot microcavity, to increase the emission rate by the Purcell effect. High quality crystals grown from solution, in addition to the creation of homogenous thin films via sublimation, have been achieved on both coated planar mirrors and fibers. Characterization of these systems has been performed, showing the effects of dispersion and cavity-coupled emission.