Research
CV Entanglement Analysis in the Superposition of Subharmonic and Second Harmonic Generation of Light with Injected Squeezed Laser Beams
In this article, we have analyzed the squeezing and statistical properties of the light gener- ated by the superposition of second harmonic light and degenerate three level squeezed laser beams. We have found that the mean photon number of the superposed light beams to be the sum of the mean photon number of that of the constituent light beams. However, the photon number variance of the superposed light beams does not happen to be the sum of the photon number variances of the separate light beams. On the other hand, the quadrature variance of the superposed light beams is the sum of the individual light beams. Furthermore, we have observed that the degree of squeezing for the superposed light beams is the average of the segregate light beams and the degree of squeezing is approximately 53.95% below the coherent state level. Even though, we have verified that the superposition of subharmonic and second harmonic light with injected degenerate three-level laser beams hehaves squeez- ing, we do not show continuous variable entanglement. But, the absence of the laser beam in the superposition state give rise entangled photons.
Cv Bipartite Entanglement of Non-Degenerate Three-Level Laser with Squeezed Modes Pumped by Coherent Light
We analyze the CV bipartite entanglement of the light generated by a coheretly pumped non degenerate three-level laser with a two-mode subharmonic generator coupled to a twomode vacuum reservoir via a single-port mirror, whose open cavity contains N non-degenerate three- level cascade atoms. We carry out our analysis by putting the noise operators associated with a vacuum reservoir in normal order. It is found that the photon-state of the system is strongly entangled at steady state where as the atom state of the system is not entangled. We have also shown that as the stimulated decay constant increases, the degree of entanglement increases. In addition, we have established that the photons in the laser cavity are highly correlated and the photon correlation and entanglement increases as the amplitude of the coherent light driving the pump mode increases. Moreover, we have realized that the presence of the subharmonic generator leads to an increase in the degree of entanglement and correlations.
A Refined Analysis of Squeezing Amplification in the One-Mode Subharmonic Generation
We have analyzed the statistical and squeezing properties of the signal mode applying the solution of c-number Langivin equations for the combination of the twin signal light beams. We have found that the mean photon number to be twofold of that of a twin signal light beam. And a large part of the mean photon number is confined in a relatively small frequency interval. In addition, we have shown that the local quadrature squeezing of the signal mode is in general greater than the global quadrature squeezing and approaches to the global quadrature squeezing as increases . Moreover, the one mode subharmonic light beams have a maximum amplified squeezing of 75% below the vacuum state level and occurs in frequency interval.
