High-gain parametric amplification for the generation of quantum states of light

The novel quantum statistical properties of the two-photon entangled states generated by spontaneous parametric downconversion have been utilized in a variety of fourth-order interferometric configurations. The extent to which the intense light produced by an unneeded parametric amplifier (optical parametric generator) retains these desirable properties is explored in a series of calculations.; Common fourth-order interferometric configurations using two-photon entangled states are summarized, with an emphasis on the Hong-Ou-Mandel and Mach-Zehnder interferometers. This summary is followed by a review of recent proposals for the exploitation of entangled states for sub-Rayleigh-limit imaging.; The limitations of using parametric downconversion at two-photon levels are discussed and the replacement of two-photon interferometric sources with the multiphoton output of a high-gain optical parametric generator is considered. The output of the Hong-Ou-Mandel interferometer, Mach-Zehnder interferometer, and quantum lithography configurations as a function of single-pass gain is determined, and the interpretation of these results in the context of multiple photon pair contributions to interferometric patterns is presented.; The analysis of the high-gain optical parametric generator as a fourth-order interferometric source is then extended to the case of multiple signal and idler output modes. The impact of the system transfer characteristics on the desired interferometric properties is discussed.; The initiation of beam filamentation by vacuum fluctuations is considered, and this four-wave mixing process is compared to parametric downconversion as a source for fourth-order interferometric applications.; We conclude by contrasting the states produced by high-gain optical parametric generation with coherent states and the states produced by seeded optical parametric amplification as sources for fourth-order interferometric configurations.