arXiv:1910.12407 · Laser Physics Letters

An improved bound for strong unitary uncertainty relations with refined sequence

Jing Li, Sujuan Zhang, Lu Liu, Chen‐Ming Bai

Published Dec 16, 2019• 7 citations

Abstract

Abstract We derive the lower bound of uncertainty relations of two unitary operators for a class of states based on the geometric-arithmetic inequality and Cauchy–Schwarz inequality. Furthermore, we propose a set of uncertainty relations for three unitary operators. Compared to the known bound introduced in Yu et al (2019 Phys. Rev . A 100 022116), the unitary uncertainty relations bound with our method is tighter, to a certain extent. Meanwhile, some examples are given in the paper to illustrate our conclusions.

DOI: 10.1088/1612-202x/ab5c22

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