71 citations · 251 across the 16 of their papers we have counts for
16 papers
Extremal positive maps on and idempotent matrices
Marek Miller, Robert Olkiewicz
A new method of analysing positive bistochastic maps on the algebra of complex matrices has been proposed. By identifying the set of such maps with a convex set of linear o…
Topology of the cone of positive maps on qubit systems
Marek Miller, Robert Olkiewicz
An alternative, geometrical proof of a known theorem concerning the decomposition of positive maps of the matrix algebra has been presented. The premise of the…
Stable subspaces of positive maps of matrix algebras
Marek Miller, Robert Olkiewicz
We study stable subspaces of positive extremal maps of finite dimensional matrix algebras that preserve trace and matrix identity (so-called bistochastic maps). We have established…
From quantum to quantum via decoherence
Ph. Blanchard, P. Lugiewicz, R. Olkiewicz
Various physical effects resulting from decoherence are discussed in the algebraic framework. In particular, it is shown that the environment may induce not only classical properti…
Decoherence induced continuous pointer states
Ph. Blanchard, R. Olkiewicz
We investigate the reduced dynamics in the Markovian approximation of an infinite quantum spin system linearly coupled to a phonon field at positive temperature. The achieved diago…
Effectively classical quantum states for open systems
Ph. Blanchard, R. Olkiewicz
Notions of robust and "classical" states for an open quantum system are introduced and discussed in the framework of the isometric-sweeping decomposition of trace class operators.…