Experimental proof of quantum Zeno-assisted noise sensing

Abstract

In the ideal quantum Zeno (QZ) effect, repeated quantum projective measurements can freeze the coherent dynamics of a quantum system. However, in the weak QZ regime, measurement back-actions can allow the sensing of semi-classical field fluctuations. In this regard, we theoretically show how to combine the controlled manipulation of a quantum two-level system, used as a probe, with a sequence of projective measurements to have direct access to the noise correlation function. We experimentally test the effectiveness of the proposed noise sensing method on a properly engineered Bose–Einstein condensate of ${}^{87}{\rm{Rb}}$ atoms realized on an atom chip. We believe that our QZ-based approach can open a new path towards novel quantum sensing devices.

Keywords

• stochastic quantum Zeno effect
• quantum noise sensing
• quantum information
• atomic physics