Controlling Electron Spin Decoherence in Nd-based Complexes via Symmetry Selection

Area of Science:

• Quantum computing
• Molecular magnetism
• Solid-state chemistry

Background:

• Long decoherence time is critical for molecular magnets in quantum computation.
• The role of local symmetry in spin decoherence is not well understood, despite its known impact on spin-lattice relaxation.

Purpose of the Study:

• To investigate the effect of local symmetry on spin decoherence in neodymium-based molecular magnets.
• To explore the relationship between local symmetry and magnetic properties.

Main Methods:

• Synthesis and characterization of two neodymium moieties with different local symmetries (C1 and C4).
• High-frequency electron paramagnetic resonance (HF-EPR) studies to determine magnetic anisotropy.
• 240 GHz Pulsed EPR studies to measure decoherence times.
• First-principle calculations to support experimental findings.

Main Results:

• Two nine-coordinated neodymium complexes, [Nd(CO3)4H2O]5-, with C1 and C4 local symmetries were synthesized.
• Both complexes exhibit easy-plane magnetic anisotropy.
• Phonon bottleneck effect is identified as crucial for magnetic relaxation.
• Higher local symmetry (C4) correlates with longer decoherence times.

Conclusions:

• Local symmetry significantly influences spin decoherence in molecular magnets.
• The study provides a pathway for designing molecular magnets with enhanced quantum coherence properties.
• Findings support the use of symmetry engineering for optimizing molecular magnets in quantum technologies.