Rotation of the polarization plane

When passing plane-polarized light through some substances, the plane of polarization can change its position in space, namely, it rotates around the light wave vector k. Substances 

Experience shows that the angle of rotation of the polarization plane p around the wave vector k in optically active media is proportional to the length I, traveled by a beam in a sample 

The coefficient a, generally dependent on the wavelength, is referred to a rotation constant and is expressed in angular degrees on millimeters of distance run. In solutions of optically active substances the angle of polarization plane rotation is proportional to the length traveled I and concentration of the active substance c  

The direction of rotation of the polarization plane depends on the substance if the plane of polarization turns clockwise in relation to k, the substance is referred to as a right-hand (or dextrorotatory) if it turns anticlockwise, the substance is a left-hand (or laevorotatory) substance. Thus the direction (the wave vector k) and the beam direction of rotation in a dextrorotatory substance forms a left-hand system, and in a laevorotatory substance forms a right-hand system. 

Research into the effects of rotation of the polarization plane is one of the methods of structural chemistry. 

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Rotation of the polarization plane (or the axes of the dichroic ellipse) by a small angle a occurs when the phases for the two circular components become different, which requires a difference in the refractive index n (Pearlman and Nguyen 1991). This effect is called circular birefringence. The change of optical rotation with wavelength is called optical rotary dispersion (ORD). 

This is the reason that in the early days optical activity meant only the rotation of the polarization plane. The first commercial CD instruments did not appear before the 1960s. 

Io(k) is the intensity of a line of the primary radiation with wavenumber k and I is the length of the atom reservoir. The sinusoidal term relates to the rotation of the polarization plane and the exponential term to the atomic absorption. As both nm and An are a function of the density of the scattering atoms, lp(k) will be proportional to the square of the density of scattering atoms (N), according to ... 

Phenomenon and Illustration Rotation of the polarized plane when linearly polarized light propagates... 

For many years it was presumed that at the inversion point, the rotation of the polarization plane by 90 occurs abraptly. This was confirmed by observations of lunar details [34]. However, Kohan [31] and Morozhenko [41, 42] have shown that the rotation of the polarization plane of light reflected by terrestrial samples takes place within some interval of phase angles Aa. The width of this interval depends on the sample morphology and composition [11]. This effect can be used in remote-sensing studies of atmosphereless celestial bodies. 

The Faraday effect is widely used for the magnetic structure visualization in transparent samples with an easy direction axis not parallel to the sample s surface [27], In this case, electromagnetic radiation passing through the domains of opposite magnetization gains slightly different rotation of the polarization plane. This enables us to visualize domains and domain walls by means... 

Yet, the optical activity must be carefully differentiated by the birefringence, but can accompany it as a perturbation . Thus, the optical activity can be investigated based on the birefringence, when one of the monochromatic plane-polarized radiations continue to be used for a new incidence on a crystal, and recording, in transmission, the rotation of the polarization plane respecting the incident polarization direction. 

Based on the director distribution we can derive the electrooptical response of a nematic liquid crystal cell (such as birefringence), rotation of the polarization plane of the incident light, total internal reflection, absorption, or some other important characteristics of the cell. In this chapter we will consider in detail these particular features of the electrooptical phenomena in uniform structures. Special attention will be paid to their possible applications. Electrooptics of the isotropic phase and polymer nematics, including Polymer Dispersed Liquid Crystals (PDLC), are also discussed. 

Biot s law determines the angle 0 of rotation of the polarization plane of light after the hquid containing the optically active component, which has the concentration Aj, travels a given length /. This law is almost additive for a mixture of optically active substances ... 

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