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The optical Hall effect manifests itself as angular momentum separation induced by the photonic spin-orbit interaction. Such a celebrated Hall effect, at the mercy of the angular momentum conservation law, has attracted tremendous interest owing to its science and potential applications in precision measurements, material characterizations, and photonic devices, as well as quantum optics. However, to date, the Hall effect only expresses angular momentum separation of the spin term (spin-spin separation) or the orbital term (orbit-orbit separation), whereas the spin-orbit angular momentum separation, named as the spin-orbit Hall effect, remains unexplored. Here we demonstrate for the first time that this spin-orbit effect could appear when the polarization state of the light beam evolves adiabatically from the equator toward the poles of the higher-order Poincaré sphere, rather than the conventional Poincaré sphere. In this scenario, the intrinsic spin and orbital components of the light beam become separated, leading to equal nonzero spin and orbital angular momenta in magnitude but with the opposite sign. We further show that the spin-orbit Hall effect can be controlled via crystal birefringence and hence holds promise for applications; e.g., it is shown that the separated orbital angular momentum could be utilized in particle manipulations.

We experimentally demonstrated the generation of orthogonally circular polarized states embedded in nonplanar geometric beams. Experimental results revealed that the production of circularly polarized beams, induced by crystal birefringence, is quantized. Numerical analyses of the polarization and the spatial morphology are consistent with the experimental results.

A polarization control method using crystal birefringence is suggested to manipulate polychromatic light. This scheme can be used with narrower bandwidth to produce various spectral effects, such as a notch filter, a flat top, and triangle-type, nipple-type, and central-frequency-dominant distributions. A modulated spectrum with greater bandwidth can be used as an optical frequency ruler, and phenomena called complementary spectra are also proposed, where the two spectral distributions, produced by rotating the polarizer, complement each other in the sense that the peaks and valleys in one spectrum are the reverse in the other. These results benefit the controlling of the spectral shape and the measurement of an unknown optical frequency.

In this chapter, we show how crystal birefringence can be used to change the polarization of an electromagnetic wave and thus obtain light in a well-defined polarization state. Various devices using this birefringence are described: linear polarizers and phase shifting plates.

Temperature (77–330 K), spectral (250–850 nm), and baric (0-500 bar) dependences of the birefringence Δny of (NH4(2BeF4 crystals are investigated. The influence of uniaxial mechanical pressures on the inversion of the birefringence Δny of (NH4(2BeF4 crystals is studied. A new method and a device to measure uniaxial stresses of up to 500 bar in the temperature range of 300–315 K based on a temperature-spectral-baric diagram of the sign inversion for the birefringence Δny of (NH4)2BeF4 crystals are proposed.

We report for the first time to our knowledge an experimental demonstration of wavelength tuning in a broadband-emitting Ti: sapphire laser crystal based on its own birefringence properties. To investigate the tuning characteristics of the spectral filter, we have used Jones-Vector formalism. The calculated wavelength-selective tuning matches very precisely the experimental observations., This research has been supported by the Spanish Government (MAT2004-03780) and the Basque Country University (UPV 13525/2001).

A discussion of materials for dispersive birefringent filters which simultaneously exhibit extremely narrow bandwidths ( \geq +45\deg acceptance angle) will be presented in this paper. Two specific types, the iso-index filter and the dispersive birefringent Lyot filter are considered. First, a figure of merit for the filter material is derived. Then the figure is related to the optical properties of the material. From this analysis the dependence of the filter bandwidth on crystal birefringence and optical bandedge characteristics is obtained.

Using the common polarization‐potential tensors and the common refractive‐index‐dispersion parameter which characterize the electro‐optical and nonlinear optical properties of all oxygen‐octahedra ferroelectrics, we analyze in detail the device behavior of electro‐optic modulators, light deflectors, and optical secondharmonic generators. General expressions for device characteristics are presented, existing materials are compared, and fundamental design limitations are emphasized. Important practical constraints related to drive circuitry and material‐fabrication difficulties are also considered. It is shown that thermal considerations impose serious constraints on the power and bandwidth capabilities of modulators and deflectors. Based on the common refractive‐index‐dispersion behavior of oxygen‐octahedra ferroelectrics, we show that in second‐harmonic‐generation applications there exists a general relationship between the crystal birefringence and the refractive index at the fundamental for collinear ph...

Far-infrared radiation generated by self-beating of a dye laser with a wide spectral width has been observed in the range of 5~30 cm-1. As mixing crystals, ZnTe, ZnSe and LiNbO3 were used. A new type of phase-matching which does not require crystal birefringence and can occur at an appropriate wavelength of incident light was found. This was experimentally verified by using four kinds of dye lasers with different central wavelengths in the range of 0.73~0.93 µm. The measured results for the three crystals are consistent with the calculated ones. A possible new scheme of simple and efficient tunable far-infrared beat generators by means of this type of phase-matching is briefly discussed.

Attempts to find the domain structure in RbH 3 (SeO 3 ) 2 have been made. A conventional polarizing microscope method of utilizing the crystal birefringence was not successful. However, by means of a dew method the clear domain structure has been found. It has been noticed that not every crystal is suitable for the observation of domain structure. Crystals grown at temperature below about 0°C are satisfactry but crystals grown at room temperature do not exhibit simple domain pattern; a probable reason for this is given.