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Abstract: Understanding of coherence properties of optical fields is of basic importance both in classical optics and in quantum physics. Coherence properties of electromagnetic laser modes are only now beginning to be explored and have not yet been tested experimentally, except in the simplest cases. In this paper, we first study theoretically the coherence properties of azimuthally polarized laser modes and we clarify the distinction between coherence and correlations in stochastic electromagnetic fields, a distinction which has up to now not been fully understood and has, in fact, been a subject of controversy. Our analysis clearly illustrates the distinction between these two concepts. After elucidating theoretically the coherence properties of radially polarized laser modes, we describe an experimental study of their properties, made by the use of a recently introduced reversed-wavefront Young’s interferometer. A good agreement between theory and experiment has been found. [Copyright &y& Elsevier]

Abstract: Polarization of SC generated by 80fs pulses of Ti:Sapphire laser strongly depends on the orientation of CaF2 plate with respect to the plane of polarization of the pump light. Intensity modulation of the broad blue-shifted wing of SC against crystal rotation for the polarization parallel and orthogonal to the polarization of the pump beam is observed with CaF2 and Sapphire. Observed modulation is due to evolution of the polarization state along the propagation distance in crystal. [Copyright &y& Elsevier]

Abstract: Detection depth and sampling volume of polarized light in highly turbid, cylindrically-shaped samples are estimated using pathlength distributions calculated from a polarization-sensitive Monte Carlo model. Due to defined ranges of the polarized light pathlength distribution, the estimated penetration depth and the interrogated volume of the polarization-maintaining photon subpopulation are smaller than those of the whole collected photon population, the latter exhibiting a wider pathlength distribution resulting from multiple scattering. It is also demonstrated that the spatial interrogation extent of polarized light in turbid media is greatly affected by the experimental detection geometry. [Copyright &y& Elsevier]

Abstract: It is commonly admitted that radial polarization leads to the best light beam focalisation in terms of spot size. The work presented here shows that the choice of polarization is in fact more subtle. As an example, it is pointed out that, for numerical apertures of focusing systems below 0.8, circular polarization induces the best light confinements in air, whereas for numerical apertures beyond 0.8, radial polarization seems to be the right solution. Moreover, for numerical apertures larger than 1, we propose an original solution to achieve the ultimate focal spots in linear optical regime. They are estimated to 0.36λ/NA (λ is the wavelength and NA is the numerical aperture), the current technological limit being around 65nm. [Copyright &y& Elsevier]

Abstract: We present a method to characterize the polarization state of a light field in the continuous-variable regime. Instead of using the abstract formalism of SU(2) quasidistributions, we model polarization as the superposition of two harmonic oscillators of the same angular frequency along two orthogonal axes, much in the classical way of dealing with this variable. By describing each oscillator by an s-parametrized quasidistribution, we derive in a consistent way the final function for the polarization. We compare with previous approaches and show how this formalism works in some relevant examples. [Copyright &y& Elsevier]

Abstract: Polarization aspects of the three-dimensional optical beam reflection and refraction at dielectric interfaces are analyzed within the framework of the aberrationless approach. The power and the transversal beam profile of the cross-polarized beam are determined in the paraxial approximation. The cross-polarization phenomenon is experimentally demonstrated. Based on the theoretical and experimental results, a simple new method using an appropriate dielectric mirror is proposed for the generation of radially polarized light beams. [Copyright &y& Elsevier]

Abstract: We show that the degree of polarization for two- and three-dimensional fields can be formulated as a distance between the field correlation matrix and the identity matrix which represents completely unpolarized light. This definition is compared with previous approaches. [Copyright &y& Elsevier]

Abstract: We introduce a scalar Wigner function for classical vectorial light fields embodying full information about polarization. We introduce global and local Stokes parameters with simple and natural transformation laws under ABCD transformations and polarization changing devices. We apply this formalism to the free propagation of vectorial Gaussian–Schell waves. [Copyright &y& Elsevier]