Scheme for generating a superposition of two- and four-photon maximally entangled states: Application to four-photon quantum photolithography
Christopher C. Gerry, Adil Benmoussa · Physical Review A · 2002
We consider the action of a beam splitter with identical degenerate parametric down converters in each of the outputs and show that with single photons injected into each of the input ports, under certain conditions, a superposition of two- and four-photon maximally entangled states may be produced. Also we describe techniques for verifying the generation of the four-photon component of the state. We then discuss the application of such states to quantum photolithography assuming the existence of substrates capable of absorbing four photons. The two-photon component makes no contribution to the background.