TENSOR PRODUCTS OF QUANTUM MAPPINGS

摘要

In this paper, we examine properties of the tensor powers of quantum mappings Φ. In particular, we review positivity properties of unitary and nonunitary qubit mappings Φ⊗2. For arbitrary finite-dimensional systems, we present the relationship between the positive and completely positive divisibility of dynamical mappings Φt⊗2documentclass[12pt]{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} egin{document}$$ {Phi}_t^{otimes 2} $$end{document} and Φt. A criterion of annihilation of entanglement by an arbitrary qubit mapping Φ⊗2 is found.