44 research outputs found
Number phase uncertainty relations: verification by homodyning
It is shown that fundamental uncertainty relations between photon number and
canonical phase of a single-mode optical field can be verified by means of
balanced homodyne measurement. All the relevant quantities can be sampled
directly from the measured phase-dependent quadrature distribution.Comment: 1 Ps figure (divided in 3 subfigures) using REVTE
Generation of phase-coherent states
An interaction scheme involving nonlinear media is suggested for
the generation of phase-coherent states (PCS). The setup is based on parametric
amplification of vacuum followed by up-conversion of the resulting twin-beam.
The involved nonlinear interactions are studied by the exact numerical
diagonalization. An experimentally achievable working regime to approximate PCS
with high conversion rate is given, and the validity of parametric
approximation is discussed.Comment: To appear in PRA -- More info at http://enterprise.pv.infn.it
s-ordered phase-sum and phase-difference distribuitons of entangled coherent states
The -ordered phase-sum and phase-difference distributions are considered
for Bell-like superpositions of two-mode coherent states. The distributions are
sensitive, respectively, to the sum and difference of the phases of the
entangled coherent states. They show loss of information about the entangled
state and may take on negative values for some orderings .Comment: 8 pages, 2 figures, iopart. accepted for publication in J. Opt. B:
Quantum Semiclass Op
The impact of co-infections on fish: a review
International audienceAbstractCo-infections are very common in nature and occur when hosts are infected by two or more different pathogens either by simultaneous or secondary infections so that two or more infectious agents are active together in the same host. Co-infections have a fundamental effect and can alter the course and the severity of different fish diseases. However, co-infection effect has still received limited scrutiny in aquatic animals like fish and available data on this subject is still scarce. The susceptibility of fish to different pathogens could be changed during mixed infections causing the appearance of sudden fish outbreaks. In this review, we focus on the synergistic and antagonistic interactions occurring during co-infections by homologous or heterologous pathogens. We present a concise summary about the present knowledge regarding co-infections in fish. More research is needed to better understand the immune response of fish during mixed infections as these could have an important impact on the development of new strategies for disease control programs and vaccination in fish