Electron and nuclear spin dynamics in antiferromagnetic molecular rings

Area of Science:

• Quantum physics
• Molecular magnetism
• Spintronics

Background:

• Antiferromagnetic molecular rings exhibit complex spin dynamics.
• Coherent tunneling of the Néel vector is a key phenomenon in these systems.
• Experimental detection of this tunneling is challenging.

Purpose of the Study:

• To theoretically investigate spin dynamics in antiferromagnetic molecular rings.
• To propose a method for detecting coherent Néel vector tunneling.
• To establish a link between spectroscopic resonances and quantum properties.

Main Methods:

• Theoretical calculation of nuclear and electronic spin correlation functions.
• Modeling the interaction between a single nuclear/impurity spin and the ring's electron spins.
• Analysis of Nuclear Magnetic Resonance (NMR) and Electron Spin Resonance (ESR) spectra.

Main Results:

• NMR and ESR techniques can detect coherent tunneling of the Néel vector.
• The position of NMR/ESR resonances directly corresponds to the tunnel splitting.
• The linewidth of these resonances provides an upper bound for electron spin decoherence rates.

Conclusions:

• NMR and ESR are powerful tools for probing quantum phenomena in molecular magnets.
• The proposed method is experimentally feasible, as demonstrated with estimates for Fe10 molecules.
• This work opens avenues for controlling and understanding spin dynamics in molecular spintronic devices.