Coherent Acoustic Control of Defect Orbital States in the Strong-Driving Limit

TL;DR

This paper demonstrates coherent control of orbital states in diamond NV centers using bulk acoustic waves, achieving strong-driving conditions and analyzing decoherence, which advances quantum control techniques for quantum networking.

Contribution

It introduces a method for coherent acoustic control of NV center orbital states in the strong-driving regime, with detailed modeling and experimental validation.

Findings

Achieved strong-driving orbital Rabi oscillations

Measured orbital decoherence times of a few nanoseconds

Validated models with experimental data and simulations

Abstract

We use a bulk acoustic wave resonator to demonstrate coherent control of the excited orbital states in a diamond nitrogen-vacancy (NV) center at cryogenic temperature. Coherent quantum control is an essential tool for understanding and mitigating decoherence. Moreover, characterizing and controlling orbital states is a central challenge for quantum networking, where optical coherence is tied to orbital coherence. We study resonant multi-phonon orbital Rabi oscillations in both the frequency and time domain, extracting the strength of the orbital-phonon interactions and the coherence of the acoustically driven orbital states. We reach the strong-driving limit, where the physics is dominated by the coupling induced by the acoustic waves. We find agreement between our measurements, quantum master equation simulations, and a Landau-Zener transition model in the strong-driving limit. Using perturbation theory, we derive an expression for the orbital Rabi frequency versus acoustic drive strength that is non-perturbative in the drive strength and agrees well with our measurements for all acoustic powers. Motivated by continuous wave spin resonance-based decoherence protection schemes, we model the orbital decoherence and find good agreement between our model and our measured few-to-several nanoseconds orbital decoherence times. We discuss the outlook for orbital decoherence protection.