Abstract
We predict that the phase-dependent error distribution of locally unentangled quantum states directly affects quantum parameter estimation accuracy. Therefore, we employ the displaced squeezed vacuum (DSV) state as a probe state and investigate an interesting question of the phase-sensitive nonclassical properties in the DSV’s metrology. We found that the accuracy limit of parameter estimation is a function of the phase-sensitive parameter $\phi - \theta /2$ with a period $\pi$. We show that when $\phi -\theta /2\ \in [ k\pi /2,3k\pi /4 )( k\in \mathbb{Z} )$, we can obtain the accuracy of parameter estimation approaching the ultimate quantum limit through the use of the DSV state with the larger displacement and squeezing strength, whereas when $\phi -\theta /2\ \in ( 3k\pi /4,k\pi ]( k\in \mathbb{Z} )$, the optimal estimation accuracy can be acquired only when the DSV state degenerates to a squeezed vacuum state.
© 2021 Optical Society of America
Full Article | PDF ArticleMore Like This
Shuai Wang and Hong-yi Fan
J. Opt. Soc. Am. B 29(7) 1672-1679 (2012)
Richard J. Birrittella, Jason Ziskind, Edwin E. Hach, Paul M. Alsing, and Christopher C. Gerry
J. Opt. Soc. Am. B 38(11) 3448-3456 (2021)
Gaurav Shukla, Karunesh Kumar Mishra, Dhiraj Yadav, Ravi Kamal Pandey, and Devendra Kumar Mishra
J. Opt. Soc. Am. B 39(1) 59-68 (2022)