Eur. Phys. J. Plus (2018) 133: 101
https://doi.org/10.1140/epjp/i2018-11936-9

Regular Article

Protecting quantum Fisher information in curved space-time

School of Economics and Management, Wuyi University, 529020, Jiangmen, China

^* e-mail: 465609785@qq.com

Received: 11 August 2017
Accepted: 12 February 2018
Published online: 12 March 2018

Abstract

In this work, we investigate the quantum Fisher information (QFI) dynamics of a two-level atom interacting with quantized conformally coupled massless scalar fields in de Sitter-invariant vacuum. We first derive the master equation that governs its evolution. It is found that the QFI decays with evolution time. Furthermore, we propose two schemes to protect QFI by employing prior weak measurement (WM) and post measurement reversal (MR). We find that the first scheme can not always protect QFI and the second scheme has prominent advantage over the first scheme.