Reverse coherent information and its properties

• 来源期刊: 中国科学:物理学 力学 天文学（英文版）
• 年，卷（期）: 2018,（1）
• 页码范围: 68-71
• 页数: 4页
• 语种: 英文

摘要

Channel capacity is a core problem in information theory [1,2].The capacity of a classical channel is essentially characterized by maximum transmission rate of classical information [1].However,in quantum information theory,several capacities can be defined for a quantum channel based on the type of information being sent.Currently,classical capacity [3,4],entanglement-assisted classical capacity [5],quantum capacity [6,7],and private capacity [7] are used to define a quantum channel.With several recent studies,the capacities themselves can exhibit nonadditivity,thereby capturing optimal performance only by a multiletter formula [8-11].Thus,no accurate formula is used to calculate the additive capacity.Recently,García-Patrón et al.[12] considered the additive capacity of a quantum channel by reverse coherent information.This channel capacity is extremely interesting and valuable,since it is explicitly computed and has been proven to be the lower bound of reverse secret-key capacity for general quantum channel [13,14].