Enhanced phonon blockade in a weakly-coupled hybrid system via mechanical parametric amplification

TL;DR

This paper demonstrates how mechanical parametric amplification can significantly enhance phonon blockade in a weakly-coupled hybrid spin-mechanical system, enabling efficient single-phonon sources for quantum applications.

Contribution

It introduces a method to achieve strong phonon blockade in weak-coupling regimes using parametric amplification and two-phonon interactions in a hybrid system.

Findings

Strong phonon blockade achieved with large mean phonon number

Enhanced anharmonicity via mechanical parametric amplification

Flexible control of phonon statistics through amplification strength

Abstract

We propose how to achieve strong phonon blockade (PB) in a hybrid spin-mechanical system in the weak-coupling regime. We demonstrate the implementation of magnetically-induced two-phonon interactions between a mechanical cantilever resonator and an embedded nitrogen-vacancy (NV) center, which, combined with parametric amplification of the mechanical motion, produces significantly enlarged anharmonicity in the eigenenergy spectrum. In the weak-driving regime, we show that strong PB appears in the hybrid system along with a large mean phonon number, even in the presence of strong mechanical dissipation. We also show flexible tunability of phonon statistics by controlling the strength of mechanical parametric amplification. Our work opens up prospects for the implementation of an efficient single-phonon source, with potential applications in quantum phononics and phononic quantum networks.