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تسجيل مستخدم جديدResolving Remoter Nuclear Spins in a Noisy Bath by Dynamical Decoupling Design
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We experimentally resolve several weakly coupled nuclear spins in diamond using a series of novelly designed dynamical decoupling controls. Some nuclear spin signals, hidden by decoherence under ordinary dynamical decoupling controls, are shifted forward in time domain to the coherence time range and thus rescued from the fate of being submerged by the noisy spin bath. In this way, more and remoter single nuclear spins are resolved. Additionally, the field of detection can be continuously tuned on sub-nanoscale. This method extends the capacity of nanoscale magnetometry and may be applicable in other systems for high-resolution noise spectroscopy.
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Dynamical decoupling (DD) is a powerful method for controlling arbitrary open quantum systems. In quantum spin control, DD generally involves a sequence of timed spin flips ($pi$ rotations) arranged to average out or selectively enhance coupling to t
he environment. Experimentally, errors in the spin flips are inevitably introduced, motivating efforts to optimise error-robust DD. Here we invert this paradigm: by introducing particular control errors in standard DD, namely a small constant deviation from perfect $pi$ rotations (pulse adjustments), we show we obtain protocols that retain the advantages of DD while introducing the capabilities of quantum state readout and polarisation transfer. We exploit this nuclear quantum state selectivity on an ensemble of nitrogen-vacancy centres in diamond to efficiently polarise the $^{13}$C quantum bath. The underlying physical mechanism is generic and paves the way to systematic engineering of pulse-adjusted protocols with nuclear state selectivity for quantum control applications.
The dynamics of single electron and nuclear spins in a diamond lattice with different 13C nuclear spin concentration is investigated. It is shown that coherent control of up to three individual nuclei in a dense nuclear spin cluster is feasible. The
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