Experimental sub-Rayleigh resolution by an unseeded high-gain optical parametric amplifier for quantum lithography

TL;DR

This paper demonstrates that a high-gain optical parametric amplifier can produce intense quantum states with sub-Rayleigh resolution, advancing quantum lithography by experimentally confirming quantum features at high gain levels.

Contribution

It experimentally shows that high-gain optical parametric amplifiers can generate intense quantum states with sub-Rayleigh fringes, enhancing quantum lithography capabilities.

Findings

Sub-Rayleigh fringes observed at high gain levels

Visibility improved via three-photon absorption

Quantum features maintained in intense multiphoton states

Abstract

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 a gain values up to 2.5. The visibility has then been increased by means of three-photon absorption. The present article opens interesting perspectives for the implementation of such an advanced interferometrical setup.