Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1866984 | Physics Letters A | 2012 | 5 Pages |
Abstract
Let HA⊗HBHA⊗HB be a bipartite system and ρABρAB a quantum state on HA⊗HBHA⊗HB, ρA=TrB(ρAB)ρA=TrB(ρAB), ρB=TrA(ρAB)ρB=TrA(ρAB). Then each quantum operation ΦBΦB on the quantum system HBHB can induce a quantum ensemble {(pμ,ρA,μ)}{(pμ,ρA,μ)} on quantum system HAHA. In this Letter, we show that the Holevo quantity χ{(pμ,ρA,μ)}χ{(pμ,ρA,μ)} of the quantum ensemble {(pμ,ρA,μ)}{(pμ,ρA,μ)} can be upper bounded by both subsystem entropies. By using the result, we answer partly a conjecture of Fannes, de Melo, Roga and Życzkowski.
► A universal upper bound of quantum ensemble is obtained. ► Using the result, a conjecture is answered partly. ► A characterization of positivity of an operator matrix is discussed.
Related Topics
Physical Sciences and Engineering
Physics and Astronomy
Physics and Astronomy (General)
Authors
Lin Zhang, Junde Wu, Shao-Ming Fei,