Giant Violations of Classical Inequalities through Conditional Homodyne Detection of the Quadrature Amplitudes of Light

Abstract

Conditional homodyne detection is proposed as an extension of the intensity correlation technique introduced by Hanbury-Brown and Twiss [Nature (London) 177, 27 (1956)]. It detects giant quadrature amplitude fluctuations for weakly squeezed light, violating a classical bound by orders of magnitude. Fluctuations of both quadrature amplitudes are anomalously large. The squeezed quadrature also exhibits an anomalous phase.

Nonclassical Correlation Properties of Radiation Fields

“…Such correlations have been studied in the resonance fluorescence of a single atom [24] and their measurement has been analyzed [25,26]. A recently proposed method of balanced homodyne correlation measurements combines the advantages of balanced homodyning with those of correlation techniques [27].…”

“…Note that nonclassical correlations of intensity and field strength of lowest order have been discussed under special conditions, such as for Gaussian fluctuations [26].…”

Vacuum fluctuations and the conditional homodyne detection of squeezed light

“…We know, however, that there is a physical distinction between vacuum fluctuations and classical noise: a classical noise field causes a photodetector to fire; vacuum fluctuations, on the other hand, do not. The difference is important where the measurement of squeezing is concerned, and particularly so when conditional homodyne detection is used, since in this case the data taking is triggered by a photocount [9,10].…”

Time evolution and squeezing of the field amplitude in cavity QED

“…In order to generalize to other phases one must either drive the system off resonance or add a coherent offset like the one discussed in Ref. [1].…”