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Will spin-relaxation times in molecular magnets permit quantum information processing?

Arzhang Ardavan·Olivier Rival·John J. L. Morton·Stephen J. Blundell·Alexei M. Tyryshkin·Grigore A. Timco·Richard E. P. Winnpenny
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Abstract

Using X-band pulsed electron spin resonance, we report the intrinsic spin-lattice ($T_1$) and phase coherence ($T_2$) relaxation times in molecular nanomagnets for the first time. In Cr$_7M$ heterometallic wheels, with $M$ = Ni and Mn, phase coherence relaxation is dominated by the coupling of the electron spin to protons within the molecule. In deuterated samples $T_2$ reaches 3 $μ$s at low temperatures, which is several orders of magnitude longer than the duration of spin manipulations, satisfying a prerequisite for the deployment of molecular nanomagnets in quantum information applications.

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Arzhang Ardavan, Olivier Rival, John J. L. Morton, Stephen J. Blundell, Alexei M. Tyryshkin, Grigore A. Timco, Richard E. P. Winnpenny. 2007-01-16. Will spin-relaxation times in molecular magnets permit quantum information processing?. https://doi.org/10.1103/physrevlett.98.057201

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