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arXiv · 1807.10270

Unveiling the limits in the coherence of spin qubits against magnetic noise

L. Escalera-Moreno·A. Gaita-Ariño·E. Coronado
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Abstract

The realization of spin-based logical gates crucially depends on magnetically-coupled spin qubits. Thus, understanding decoherence when spin qubits are in close proximity will become a roadblock to overcome. Herein, we provide a general first-principles model that straightforwardly evaluates the spin bath effect on the qubit phase memory time $T_m$ . The method is applied to a ground-spin $J=8$ magnetic molecule 1 displaying atomic clock transitions, which remarkably increase $T_m$ at unusually high spin concentrations. Besides reproducing experimental $T_m$ values calculated by recent models in simple spin-1/2 systems, our approach unveils the causes that limit the coherence reached at the clock transitions in more challenging systems such as 1, where these previous models fail.

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L. Escalera-Moreno, A. Gaita-Ariño, E. Coronado. 2018-07-26. Unveiling the limits in the coherence of spin qubits against magnetic noise. https://doi.org/10.1103/physrevb.100.064405

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