Enhanced measurement precision with continuous interrogation during dynamical decoupling

TL;DR

This paper introduces a phase relay method (PRM) that enables continuous interrogation of DC signals during dynamical decoupling, significantly improving measurement sensitivity in quantum sensing applications.

Contribution

The work presents a novel phase relay method that overcomes the limitations of dynamical decoupling in DC measurements, enabling continuous interrogation and enhanced sensitivity.

Findings

Achieves sensitivities near SQL and HL for 10,000 atoms

Suppresses ambient noise using DD techniques

Demonstrates practical application in quantum sensing

Abstract

Dynamical decoupling (DD) is normally ineffective when applied to DC measurement. In its straightforward implementation, DD nulls out DC signal as well while suppressing noise. This work proposes a phase relay method (PRM) that is capable of continuously interrogating the DC signal over many DD cycles. We illustrate its efficacy when applied to measurement of a weak DC magnetic field with an atomic spinor Bose-Einstein condensate. Sensitivities approaching standard quantum limit (SQL) or Heisenberg limit (HL) are potentially realizable for a coherent spin state (CSS) or a squeezed spin state (SSS) of 10,000 atoms respectively, while ambient laboratory level noise is suppressed by DD. Our work offers a practical approach to mitigate the limitations of DD to DC measurement and will like find other applications for resorting coherence in quantum sensing and quantum information processing research.