Geometrically induced singular behavior of entanglement
Daniel Cavalcanti, Pablo L. Saldanha, Olavo Cosme, Fernando G. S. L. Brandão, Carlos Henrique Monken, Sebastião Pádua, Marcelo França Santos, Marcelo Terra Cunha · Physical Review A · 2008
We show that the geometry of the set of quantum states plays a crucial role in the behavior of entanglement in different physical systems. More specifically, it is shown that singular points at the border of the set of unentangled states originate singularities in the dynamics of entanglement of smoothly varying quantum states. We illustrate this result by implementing a photonic parametric down-conversion experiment. Moreover, this effect is connected to recently discovered singularities in condensed matter models.