Hybrid continuous dynamical decoupling: a photon-phonon doubly dressed spin

TL;DR

This paper demonstrates a hybrid spin-oscillator system where strain-mediated coupling enhances coherence times of nitrogen-vacancy spins, enabling improved quantum information processing and sensing capabilities.

Contribution

It introduces a novel hybrid continuous dynamical decoupling method using photon-phonon dressing to significantly extend spin coherence times.

Findings

Spin Rabi frequency locks to oscillator mode in the MHz range.

Decoherence times increase by two orders of magnitude.

Potential for further prolonging dephasing times to relaxation limits.

Abstract

We study the parametric interaction between a single Nitrogen-Vacancy electronic spin and a diamond mechanical resonator in which the spin is embedded. Coupling between spin and oscillator is achieved by crystal strain, which is generated upon actuation of the oscillator and which parametrically modulates the spins' energy splitting. Under coherent microwave driving of the spin, this parametric drive leads to a locking of the spin Rabi frequency to the oscillator mode in the megahertz range. Both the Rabi oscillation decay time and the inhomogeneous spin dephasing time increase by two orders of magnitude under this spin-locking condition. We present routes to prolong the dephasing times even further, potentially to the relaxation time limit. The remarkable coherence protection that our hybrid spin-oscillator system offers is reminiscent of recently proposed concatenated continuous dynamical decoupling schemes and results from our robust, drift-free strain-coupling mechanism and the narrow linewidth of the high-quality diamond mechanical oscillator employed. Our findings suggest feasible applications in quantum information processing and sensing.