  We experimentally show how classical correlations can be turned into quantum
entanglement, via the presence of non-unital local noise and the action of a
CNOT gate. We first implement a simple two-qubit protocol in which entanglement
production is not possible in the absence of local non-unital noise, while
entanglement arises with the introduction of noise, and is proportional to the
degree of noisiness. We then perform a more elaborate four-qubit experiment, by
employing two hyperentangled photons initially carrying only classical
correlations. We demonstrate a scheme where the entanglement is generated via
local non-unital noise, with the advantage to be robust against local unitaries
performed by an adversary.
