Coherent spin dynamic of strongly correlated defects in spin chains.*

The quantum coherence of spins is usually studied in highly diluted magnetic ions in a diamagnetic medium. We propose a new paradigm: a non-magnetic defect, like a break in the translational symmetry of Heisenberg’s spin chain, polarized many spins around it.
We show that this correlated spin system that is made of hundreds of coupled spins bear an overall spin S = 1/2 and can be manipulated as a single spin. By means of pulsed electron paramagnetic resonance, we show the quantum coherence of this object by measuring the Rabi oscillations. We show that the spin bath decoherence is strongly reduced by the strong isotropic exchange interaction.

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2. L. Soriano, et al. Applied Magnetic Resonance (2020), arXiv:2008.10897.