Quantifying coherence of quantum measurements. (8th September 2020)

• Record Type: Journal Article
• Authors: Baek, Kyunghyun; Sohbi, Adel; Lee, Jaehak; Kim, Jaewan; Nha, Hyunchul
• Is Part Of: New journal of physics. Volume 22:Number 9(2020:Sep.)
• Publication Date: 2020-09-08
• Subjects: quantum coherence -- quantum measurements -- quantum foundations -- resource theories -- quantum information; Physics -- Periodicals; Physics; Periodicals; 530.05
• DOI: 10.1088/1367-2630/abad7e
• Languages: English
• ISSNs: 1367-2630

Abstract

Abstract: In this work we investigate how to quantify the coherence of quantum measurements. First, we establish a resource theoretical framework to address the coherence of measurement and show that any statistical distance can be adopted to define a coherence monotone of measurement. For instance, the relative entropy fulfills all the required properties as a proper monotone. We specifically introduce a coherence monotone of measurement in terms of off-diagonal elements of positive-operator-valued measure components. This quantification provides a lower bound on the robustness of measurement-coherence that has an operational meaning as the maximal advantage over all incoherent measurements in state discrimination tasks. Finally, we propose an experimental scheme to assess our quantification of measurement-coherence and demonstrate it by performing an experiment using a single qubit on IBM Q processor.