Robust Noise Suppression and Quantum Sensing by Continuous Phased Dynamical Decoupling

TL;DR

This paper introduces continuous phased dynamical decoupling (CPDD), a novel method for quantum sensing that enhances noise suppression and frequency estimation precision without using short pulses, suitable for high-field NMR and quantum systems.

Contribution

The paper presents the experimental demonstration of CPDD, a new continuous control technique with phase modulation that improves robustness and precision in quantum sensing applications.

Findings

Successfully applied CPDD to nanoscale NMR.

Achieved microhertz frequency estimation uncertainty.

Expanded dynamical decoupling applicability to various quantum systems.

Abstract

We propose and demonstrate experimentally continuous phased dynamical decoupling (CPDD), where we apply a continuous field with discrete phase changes for quantum sensing and robust compensation of environmental and amplitude noise. CPDD does not use short pulses, making it particularly suitable for experiments with limited driving power or nuclear magnetic resonance at high magnetic fields. It requires control of the timing of the phase changes, offering much greater precision than the Rabi frequency control needed in standard continuous sensing schemes. We successfully apply our method to nanoscale nuclear magnetic resonance and combine it with quantum heterodyne detection, achieving microhertz uncertainty in the estimated signal frequency for a 120 s measurement. Our Letter expands significantly the applicability of dynamical decoupling and opens the door for a wide range of experiments, e.g., in nitrogen-vacancy centers, trapped ions, or trapped atoms.