Search results for "Stokes parameters"
showing 4 items of 14 documents
The dependence of dichroism in VUV-photoemission on the optical properties of adsorbates: Cs-monolayer on W(110)
1998
Abstract We report on the dependence of dichroic photoemission excited by polarised light on the angle of photon incidence. We measured the difference in the angle-resolved photoemission intensities from Cs-5p semi-corelevels excited by photons of opposite helicity, known as CDAD and of orthogonal linear polarisation—LDAD. We found that the dependence of dichroism on the angle of incidence can not be described by the equations used in the photoemission model for free atomic states. A complex consideration of the parallel and perpendicular components of the vector potential of the exciting light is needed, including the phase shift between these components. The phase shift is produced by the…
3D digitization of transparent objects by polalization techniques in IR & by triangulation in UV
2011
Two non-conventional methods for the 3D digitization of transparent objects via non-contact measurement are reported in this thesis. 3D digitization is a well acknowledged technique for opaque objects and various commercial solutions based on different measurement approaches are available in the market offering different types of resolution at different prices. Since these techniques require a diffused or lambertian surface, their application to transparent surfaces fails. Indeed, rays reflected by the transparent surface are perturbed by diverse inter-reflections induced by the refractive properties of the object. Therefore, in industrial applications like quality control, the transparent …
Radio polarization maps of shell-type SNRs II. Sedov models with evolution of turbulent magnetic field
2017
Polarized radio emission has been mapped with great detail in several Galactic supernova remnants (SNRs), but has not yet been exploited to the extent it deserves. We have developed a method to model maps of the Stokes parameters for shell-like SNRs during their Sedov evolution phase. At first, 3-dimensional structure of a SNR has been computed, by modeling the distribution of the magnetohydrodynamic parameters and of the accelerated particles. The generation and dissipation of the turbulent component of magnetic field everywhere in SNR are also considered taking into account its interaction with accelerated particles. Then, in order to model the emission, we have used a generalization of t…
Fiber optical parametric polarizer
2013
In this work, a fiber-optical parametric polarizer (FOPP), i.e., a polarizing device based on parametric amplification in optical fibers is demonstrated. This was achieved for both the signal and idler waves with 25 dB gain over a broad bandwidth using the strong polarization-dependent gain (PDG) of parametric amplifiers. The experimental values of the degree of polarization (DOP) calculated from the Stokes parameters are indicated above each sphere. The gain spectra are also plotted with the parametric gain and the signal OSNR in insets. The Poincare sphere represents the three normalized Stokes parameters (S1,S2,S3) in unit radius. Results show that he DOP of the signal significantly incr…