Optical spin-state polarization in a binuclear europium complex towards molecule-based coherent light-spin interfaces

Area of Science:

• Quantum Information Processing (QIP)
• Solid-State Materials Science
• Molecular Quantum Systems

Background:

• Solid-state optical quantum information processing (QIP) requires suitable resonant optical materials.
• Rare-earth ion (REI)-based molecular systems offer tunable quantum properties via molecular engineering.
• Efficient initialization and addressing of nuclear spins are fundamental for all-optical QIP.

Purpose of the Study:

• To demonstrate efficient polarization of ground-state nuclear spins in a binuclear Eu(III) complex.
• To investigate the optical properties of the 5D0 → 7F0 transition for QIP applications.
• To assess the potential of molecule-based systems for coherent light-spin QIP interfaces.

Main Methods:

• Utilized a binuclear Europium(III) complex with an inhomogeneously broadened 5D0 → 7F0 optical transition.
• Performed spectral hole burning experiments at 1.4 K to analyze optical and spin properties.
• Measured homogeneous linewidth (Γh), optical coherence lifetime (T2opt), and ground-state spin population lifetime (T1spin).

Main Results:

• Achieved efficient polarization of ground-state nuclear spins.
• Burnt long-lived spectral holes with a homogeneous linewidth (Γh) of 22 ± 1 MHz.
• Obtained an optical coherence lifetime (T2opt) of 14.5 ± 0.7 ns and a ground-state spin population lifetime (T1spin) of 1.6 ± 0.4 s.

Conclusions:

• The study demonstrates a significant advancement in developing molecule-based materials for QIP.
• Efficient nuclear spin polarization and long coherence times were achieved in the Eu(III) complex.
• These findings represent a progressive step towards realizing molecule-based coherent light-spin QIP interfaces.