Molecule-based coherent light-spin interfaces for quantum information processing – optical spin state polarization in a binuclear Europium complex

Abstract

The success of the emerging field of solid-state optical quantum information processing (QIP) critically depends on the access to resonant optical materials. Rare-earth ion (REI)- based molecular systems, whose quantum properties could be tuned taking advantage of molecular engineering strategies, are one of the systems actively pursued for the implementation of QIP schemes. Herein, we demonstrate the efficient polarization of 2 ground-state nuclear spins—a fundamental requirement for all-optical spin initialization and addressing—in a binuclear Eu(III) complex, featuring inhomogeneously broadened 5D0→7 F0 optical transition. At 1.4 K, long-lived spectral holes have been burnt in the transition: homogeneous linewidth (Γh) = 22 +/- 1 MHz, which translates as optical coherence lifetime (T2opt) = 14.5 +/- 0.7 ns, and ground-state spin population lifetime (T1spin) = 1.6 +/- 0.4 s have been obtained. The results presented in this study are a progressive step towards the realization of molecule-based coherent light-spin QIP interfaces.

Microcavity-Modified Emission from Rare-Earth Ion-Based Molecular Complexes

“…Moreover, the versatility of these molecular complexes, facilitated by the easily tunable chemical and electronic structures of the surrounding ligands, [8][9][10][11] may provide opportunities for tailor-made quantum systems with minimal nuclear spins and high brightness. Recent demonstrations of long-lived spectral holes in such molecular complex ensembles 12 attest the potential to establish light-spin interfaces in these materials, making them interesting alternative platforms beyond rare-earth ion doped macroscopic bulk materials.…”