Extreme points of the set of density matrices with positive partial transpose
Jon Magne Leinaas, Jan Myrheim, Eirik Ovrum · Physical Review A · 2007
We present a necessary and sufficient condition for a finite-dimensional density matrix to be an extreme point of the convex set of density matrices with positive partial transpose with respect to a subsystem. We also give an algorithm for finding such extreme points and illustrate this by some examples.