Amending coherence-breaking channels via unitary operations

Long-Mei Yang, Bin Chen, Shao-Ming Fei, and Zhi-Xi Wang

Contact the author: Please use for correspondence this email.
Submission date: 09. Jan. 2019
Pages: 10
published in: International journal of theoretical physics, 57 (2018) 12, p. 3776-3784 
DOI number (of the published article): 10.1007/s10773-018-3890-4
Bibtex
Download full preprint: PDF (87 kB)

Abstract:
The coherence-breaking channels play a significant role in quantum information theory. We study the coherence-breaking channels for qubit systems and give a method to amend the coherence-breaking channels by applying unitary operations. For given incoherent channel Φ, we give a necessary and sufficient condition for the channel to be a coherence-breaking channel and amend it via unitary operations. For incoherent channels Φ that are not coherence-breaking ones, we consider Φ ∘ Φ and give the conditions for coherence-breaking and channel amendment as well.