11 research outputs found
Toward the multiphoton parametric oscillators
We propose novel types of parametric oscillators generating both three-photon
and four-photon bright light which are accessible for an experiment. The
devices are based on the cascaded down-conversion processes and consist of
second-order media inserted in two-resonant mode cavity. Discussion of
dissipation and quantum features of the system are performed by the
quantum-jump simulation method and concerns to the Wigner functions. The
phase-space multistabilities and critical threshold behavior of three- and
four-photon subharmonics are obtained.Comment: 3 figures, submitted to Physics Letter
Doubly--dressed atomic wave packets
The problems of cavity atom optics in the presence of an external strong
coherent field are formulated as the problems of potential scattering of
doubly-dressed atomic wave packets. Two types of potentials produced by various
multiphoton Raman processes in a high-finesse cavity are examined. As an
application the deflection of dressed atomic wave by a cavity mode is
investigated. New momentum distribution of the atoms is derived that depends
from the parameters of coherent field as well as photon states in the cavity.Comment: 6 pages,4 figure
Entangled light in transition through the generation threshold
We investigate continuous variable entangling resources on the base of
two-mode squeezing for all operational regimes of a nondegenerate optical
parametric oscillator with allowance for quantum noise of arbitrary level. The
results for the quadrature variances of a pair of generated modes are obtained
by using the exact steady-state solution of Fokker-Planck equation for the
complex P-quasiprobability distribution function. We find a simple expression
for the squeezed variances in the near-threshold range and conclude that the
maximal two-mode squeezing reaches 50% relative to the level of vacuum
fluctuations and is achieved at the pump field intensity close to the
generation threshold. The distinction between the degree of two-mode squeezing
for monostable and bistable operational regimes is cleared up.Comment: 7 pages, 4 figures; Content changed: more details added to the
discussion. To be published in Phys. Rev.
Sub-Poissonian statistics in order-to-chaos transition
We study the phenomena at the overlap of quantum chaos and nonclassical
statistics for the time-dependent model of nonlinear oscillator. It is shown in
the framework of Mandel Q-parameter and Wigner function that the statistics of
oscillatory excitation number is drastically changed in order-to chaos
transition. The essential improvement of sub-Poissonian statistics in
comparison with an analogous one for the standard model of driven anharmonic
oscillator is observed for the regular operational regime. It is shown that in
the chaotic regime the system exhibits the range of sub- and super-Poissonian
statistics which alternate one to other depending on time intervals. Unusual
dependence of the variance of oscillatory number on the external noise level
for the chaotic dynamics is observed.Comment: 9 pages, RevTeX, 14 figure
Chaos in a double driven dissipative nonlinear oscillator
We propose an anharmonic oscillator driven by two periodic forces of
different frequencies as a new time-dependent model for investigating quantum
dissipative chaos. Our analysis is done in the frame of statistical ensemble of
quantum trajectories in quantum state diffusion approach. Quantum dynamical
manifestation of chaotic behavior, including the emergence of chaos, properties
of strange attractors, and quantum entanglement are studied by numerical
simulation of ensemble averaged Wigner function and von Neumann entropy.Comment: 9 pages, 18 figure
Effects of χ(3) nonlinearities in second-harmonic generation
We investigate the effects of higher-order, chi ((3)), nonlinearities on the process of second-harmonic generation. In the traveling-wave case we find substantive differences in the macroscopic behavior of the fields when the chi ((3)) components are present. In the intracavity cage, which has been investigated before using a Linearized analysis, we investigate regions where these analyses may not be valid, comparing and contrasting the full quantum simulations with previous results