The research suggests that a relatively simple quantum set-up could be used to extract spatial information that is traditionally limited by the so-called Rayleigh ... the interference at a beam ...

WHEN radiation is scattered by a resonator, the question of its identity of frequency and coherence of phase with the incident radiation is not simply answered except for an infinitely narrow ...

Their paper, published in Physical Review Letters, proposes that classical interference arises from specific two-mode binomial states, which are collective bright and dark entangled states of light.