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Adiabatic Dynamical-Decoupling Based Control of Nuclear Spin Registers

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 نشر من قبل T.S. Monteiro
 تاريخ النشر 2021
  مجال البحث فيزياء
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The use of the nuclear spins surrounding electron spin qubits as quantum registers and long-lived memories opens the way to new applications in quantum information and biological sensing. Hence, there is a need for generic and robust forms of control of the nuclear registers. Although adiabatic gates are widely used in quantum information, they can become too slow to outpace decoherence. Here, we introduce a technique whereby adiabatic gates arise from the dynamical decoupling protocols that simultaneously extend coherence. We illustrate this pulse-based adiabatic control for nuclear spins around NV centers in diamond. We obtain a closed-form expression from Landau-Zener theory and show that it reliably describes the dynamics. By identifying robust Floquet states, we show that the technique enables polarisation, one-shot flips and state storage for nuclear spins. These results introduce a new control paradigm that combines dynamical decoupling with adiabatic evolution.

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