Protecting qubit coherence by spectrally engineered driving of the spin environment

TL;DR

This paper demonstrates a novel active decoherence mitigation method for qubits by spectrally engineering the environmental noise with a custom polychromatic drive, outperforming traditional monochromatic techniques in a solid-state defect spin system.

Contribution

It introduces a new approach of using spectral engineering of the environment with custom waveforms to protect qubit coherence, advancing active decoherence control methods.

Findings

Polychromatic drive outperforms monochromatic in decoherence mitigation.

Experimental results agree with quantitative modeling.

Path opened for environment-driven decoherence protection.

Abstract

Modern quantum technologies rely crucially on techniques to mitigate quantum decoherence; these techniques can be either passive, achieved for example via materials engineering, or active, typically achieved via pulsed monochromatic driving fields applied to the qubit. Using a solid-state defect spin coupled to a microwave-driven spin bath, we experimentally demonstrate a decoherence mitigation method based on spectral engineering of the environmental noise with a polychromatic drive waveform, and show that it outperforms monochromatic techniques. Results are in agreement with quantitative modeling, and open the path to active decoherence protection using custom-designed waveforms applied to the environment rather than the qubit.