Constructive counterexamples to the additivity of minimum output Rényi entropy of quantum channels for all p>1
Harm Derksen (Northeastern University);
Benjamin Lovitz (Concordia University)
[abstract]Abstract: We present explicit quantum channels with stictly sub-additive minimum output Rényi entropy for all p>1, improving upon prior constructions which handled p>2. Our example is provided by explicit constructions of linear subspaces with high geometric measure of entanglement. Our construction applies in both the bipartite and multipartite settings. As further applications, we use our construction to find entanglement witnesses with many highly negative eigenvalues, and to construct highly entangled mixed quantum states.
