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A quantum many body model for the embedded electron spin decoherence in organic solids
Marina Kveder1, Boris Rakvin1, Jiangyang You1
1Division of Physical Chemistry, Ruder Bošković Institute, Bijenička 54, 10000 Zagreb, Croatia.
The Journal of Chemical Physics
|November 3, 2019
Summary
This study introduces a quantum model for electron spin decoherence in organic solids, explaining how methyl group rotation affects it. The model clarifies how hindered methyl groups can either accelerate or enhance electron spin coherence, with experimental validation.
Area of Science:
- Quantum physics
- Materials science
- Chemistry
Background:
- Electron spin decoherence in organic solids is crucial for quantum technologies.
- Methyl group rotation significantly influences spin dynamics but is often oversimplified.
- Understanding these interactions is key to controlling quantum states.
Purpose of the Study:
- To develop a generalized nuclear spin bath model for embedded electron spin decoherence.
- To incorporate the influence of hindered methyl group rotation tunneling.
- To predict decoherence profiles based on molecular structure and dynamics.
Main Methods:
- Developed a quantum many-body model for nuclear spin baths.
- Utilized the cluster correlation expansion method for model resolution.
- Experimentally validated the model using methyl malonic acid and acetamide.
Main Results:
- The model accurately predicts decoherence profiles influenced by methyl group hindrance.
- Strongly hindered methyl groups accelerate decoherence via increased nuclear spin coupling.
- Weakly hindered methyl groups enhance coherence through a novel confinement mechanism.
Conclusions:
- Methyl group rotation tunneling is a critical factor in electron spin decoherence.
- The developed model provides a framework for understanding and controlling spin coherence in organic solids.
- Experimental results confirm the model's predictions for different hindrance levels.
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