Parametric processes

Carson L. Tang

Carson L. Tang, L.K. Cheng

This chapter outlines the noise source on the basis of a quantum theory. A quantum theory is, however, needed for a rigorous analysis of the spontaneous parametric scattering process and a clear understanding of the spontaneous parametric process is important for a number of reasons. First, since the frequency and phase-matching conditions for the spontaneous emission are the same as those for the corresponding stimulated parametric process, the tuning characteristics of optical parametric oscillators and amplifiers can be determined from the spontaneous parametric emission prior to the construction of an actual oscillator or amplifier. It is, however, far from clear whether such an amplifier can be made practical, although there are interesting fundamental issues related to squeezing in optical parametric processes that have attracted a great deal of attention. For optical parametric processes, one is usually interested in the transparent region of the optical media.

Atsushi Takada

After briefly introducing the application of the optical parametric process to optical communication, recent progress in parametric wavelength conversion is described. Features and issues of the phase-sensitive parametric amplifier are also mentioned.

Mário J. de Oliveira

Lele Chen, Ping Xu, Y. F. Bai +5 more

We experimentally investigated concurrent parametric downconversion processes in a two-dimensional hexagonally poled lithium tantalate crystal. The substantial enhancement of parametric gain was observed when concurrent processes shared a common parametric beam. Both degenerate and nondegenerate concurrent parametric downconversion processes were studied. Analyses of the spatial forms and output angles showed a strong dependence on the working temperature, during which a well-defined beamlike parametric output was observed. Our results will stimulate the design for coherent high-gain generation of multiple parametric beams and also shed light on the compact engineering of path-entanglement with specific spatial forms based on concurrent spontaneous parametric downconversion processes.

Jean-Claude Zambrini