The reduction of the number of incoherent Kraus operations for qutrit systems

Jiahuan Qiao, Lingyun Sun, Jing Wang, Ming Li, Shuqian Shen, Lei Li, Shaoming Fei
2020 Europhysics letters  
Quantum coherence is a fundamental property that can emerge within any quantum system. Incoherent operations, defined in terms of the Kraus decomposition, take an important role in state transformation. The maximum number of incoherent Kraus operators has been presented in [A. Streltsov, S. Rana, P. Boes, J. Eisert, Phys. Rev. Lett. 119. 140402 (2017)]. In this work, we show that the number of incoherent Kraus operators for a single qubit can be reduced from 5 to 4 by constructing a proper
more » ... ry matrix. For qutrit systems we further obtain 32 incoherent Kraus operators, while the upper bound in the research of Sterltsov gives 39 Kraus operators. Besides, we reduce the number of strictly incoherent Kraus operators from more than 15 to 13. And we consider the state transformation problem for these two types of operations in single qutrit systems.
doi:10.1209/0295-5075/129/60006 fatcat:3ojclx6smnbiraatdh6d6i3mfe