Continuous dynamical decoupling of a single diamond nitrogen-vacancy center spin with a mechanical resonator
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2015-10-05 |
| Journal | arXiv (Cornell University) |
| Authors | E. R. MacQuarrie, Tanay A. Gosavi, Sunil A. Bhave, Gregory D. Fuchs |
Abstract
Section titled āAbstractāInhomogeneous dephasing from uncontrolled environmental noise can limit the coherence of a quantum sensor or qubit. For solid state spin qubits such as the nitrogen-vacancy (NV) center in diamond, a dominant source of environmental noise is magnetic field fluctuations due to nearby paramagnetic impurities and instabilities in a magnetic bias field. In this work, we use ac stress generated by a diamond mechanical resonator to engineer a dressed spin basis in which a single NV center qubit is less sensitive to its magnetic environment. For a qubit in the thermally isolated subspace of this protected basis, we prolong the dephasing time $T_2^$ from $2.7\pm0.1$ $Ī¼$s to $15\pm1$ $Ī¼$s by dressing with a $Ī©=581\pm2$ kHz mechanical Rabi field. Furthermore, we develop a model that quantitatively predicts the relationship between $Ī©$ and $T_2^$ in the dressed basis. Our model suggests that a combination of magnetic field fluctuations and hyperfine coupling to nearby nuclear spins limits the protected coherence time over the range of $Ī©$ accessed here. We show that amplitude noise in $Ī©$ will dominate the dephasing for larger driving fields.