Classical Theory of Non-ideal Coherent Light Beams

Richard J. Fitzgerald

Ruo-Ding Li, S -K Choi, Prem Kumar

A Gaussian wave theory is developed to analyse the sub-Poissonian light generated by means of a travelling-wave optical parametric deamplification. The Gaussian spatial profile of the pump beam limits the observable Fano factor to -3 dB (0.5). Gain-induced diffraction of the signal beam and classical fluctuations of the pump-signal relative phase cause further degradation. The theory is compared with our recent experimental results, and excellent agreement is found after the effect of non-ideal photoelectron efficiency is taken into account.

Hari Prakash, Devendra Kumar Mishra

We present here an example where a non-classical feature of a light beam is enhanced simply by mixing with another classical coherent light beam using a beam splitter. This non-classical feature is amplitude-squared squeezing of a Gaussian light beam expressed by a negative value of or a negative value of the normalized quantity which can become more negative on enhancement. Here, , where and are the density, annihilation and creation operators, respectively.

Daniela Dragoman, Mircea Dragoman

Partha Ghose

Baris I. Erkmen, Jeffrey H. Shapiro

Optical coherence theory for the complex envelopes of passband fields has been concerned, almost exclusively, with correlations that are all phase insensitive, despite decades of theoretical and experimental work on the generation and applications of light with phase-sensitive correlations. This paper begins the process of remedying that deficiency, by developing coherence theory for classical scalar fields with phase-sensitive fluctuations. In particular, the Wolf equations are extended to phase-sensitive fields, paraxial free-space propagation effects are analyzed, and a normal-mode decomposition for scalar fields of arbitrary coherence is established. The extension of this theory to the field-operator description that is needed to characterize non-classical light beams is briefly discussed.