1210.0644 (Scott M. Cohen)

Sums of product operators that remain product operators    [PDF]

Scott M. Cohen

We give a necessary condition that a sum of product operators is itself a product operator. This condition turns out to have a variety of useful and interesting applications in the field of quantum information, including a characterization of separable quantum channels and a constraint on when an operator sum representation of a separable quantum channel in terms of product operators is a unique product representation.

View original: http://arxiv.org/abs/1210.0644