2024/12/10 by Zhi‐Xiang Jin, Yuan-Hong Tao, Jin, Zhi-Xiang +5 · 1 citation
Engineering · #Geophysics and Sensor Technology
paper · pdf · doi:10.48550/arxiv.2412.07449
In the quantitative theory of quantum coherence, the amount of coherence for given states can be meaningfully discussed only when referring to a preferred basis. One of the objections to this quantification is that the amount of coherence is an intrinsically basis-dependent quantity. This limitation can, however, be lifted when considering a set of quantum states invariant under arbitrary unitary transformations. Thus, we analyze a basis-independent definition of quantum coherence, and the incoherent state is taken as the maximally mixed state. We describe the relationship between the basis-independent and the basis-dependent approaches and give several applications to show the advantages of the former method. The relations among basis-independent coherence, quantum entanglement, and quantum discord are discussed by using the relative entropy within a multipartite system.