Experimental sub-Rayleigh resolution by an unseeded high-gain optical parametric amplifier for quantum lithography
Fabio Sciarrino, Chiara Vitelli, F. De Martini, Ryan T. Glasser, Hugo V. Cable, Jonathan P. Dowling · Physical Review A · 2008
Quantum lithography proposes to adopt entangled quantum states in order to increase resolution in interferometry. In the present paper we experimentally demonstrate that the output of a high-gain optical parametric amplifier can be intense yet exhibits quantum features, namely, sub-Rayleigh fringes, as proposed by [Agarwal et al., Phys. Rev. Lett. 86, 1389 (2001)]. We investigate multiphoton states generated by a high-gain optical parametric amplifier operating with a quantum vacuum input for gain values up to 2.5. The visibility has then been increased by means of three-photon absorption. The present paper opens interesting perspectives for the implementation of such an advanced interferometrical setup.