Citation: Shen, Yang & Wang, Ping & Cheung, Chun & Wachtrup, Joerg & Liu, Ren-Bao & Yang,
Sen. (2023). Detection of quantum signals free of classical noise via quantum correlation.
10.48550/arXiv.2302.13530.
Authors: Yang Shen, Ping Wang, Chun Tung Cheung, Jörg Wrachtrup, Ren-Bao Liu and Sen Yang
Publication location: PHYSICAL REVIEW LETTERS 130
Year (date): 2023
D.O.I: 10.1103/PhysRevLett.130.070802
Abstract: Extracting useful signals is key to both classical and quantum technologies. Conventional noise filtering methods rely on different patterns of signal and noise in frequency or time domains, thus limiting their scope of application, especially in quantum sensing. Here, we propose a signal-nature-based (not signal pattern-based) approach which singles out a quantum signal from its classical noise background by employing the intrinsic quantum nature of the system. We design a novel protocol to extract the quantum correlation signal
and use it to single out the signal of a remote nuclear spin from its overwhelming classical noise backgrounds, which is impossible to be accomplished by conventional filter methods. Our Letter demonstrates the quantum or classical nature as a new degree of freedom in quantum sensing. The further generalization of this quantum nature-based method opens a new direction in quantum research.