Right-hand polarized wave

The polarization ellipse along with a designation of the rotation direction (right- or left-handed) fully describes the temporal evolution of the real electric vector at a fixed point in space. This evolution can also be visualized by plotting the curve in (9,tp,t) coordinates described by the tip of the electric vector as a function of time. For example, in the case of an elliptically polarized plane wave with right-handed polarization, the curve is a right-handed helix with an elliptical projection onto the Ocp - plane centered around... 

Figure 8.2 (a) The helix described by the tip of the real electric vector of a plane electromagnetic wave with right-handed polarization in 0, (p, t) coordinates at a fixed point in space, (b) As in (a), but in 6, (p, s) coordinates at a fixed moment in time, (c) As in (b), but for a linearly polarized wave. 

In practice, the quality of polarization of an antenna is described by the axial ratio (AR), which provides the same information as the absolute value of the eccentricity r. The sign of z represents the sense of rotation if t > 0 we have a right-hand polarized (RHP) wave, while if t < 0 the sense is left-hand polarized (LHP). The axial ratio is defined for circular polarization and for linear polarization. 

Circular polarization of a wave can occur in two directions right or left. For a right circularly polarized wave, the rotation of the electric field vector observed in the direction towards the source occurs in a clockwise sense the tip of the vector draws a right-handed helix while propagating in space. In the case of a left circularly polarized wave, the rotation of the electric field vector observed in the direction towards the source is counterclockwise the tip of the propagating vector draws a left-handed helix (Fig. 6.2). Therefore, a circularly polarized wave can be considered as a radiation possessing chirality. 

Fig. 21 Spiral structiu-e formed by seven beam interference central beam is right-handed circularly polarized, and the side beams linearly [32,33]. Simulated by interference of plane waves according to Eq. 2 with side beams comprising an 80° angle with the optical axis (the -field of the central beam is Eo = o/V2(l, i,0), where + corresponds to the right-handedness i = V )...

Figure B3.5.3 The relation of ellipticity to the differential absorption of circularly polarized radiation. The oscillating radiation sine wave, 01, is proceeding out of the plane of the paper towards the viewer. (A) Plane-polarized radiation is made up of left- and right-handed circularly polarized components, OL and OR, respectively. Absorption by a chromophore in a nonchiral environment results in an equal reduction in intensity of each component, whose resultant is a vector oscillating only in the vertical plane—i.e., plane-polarized radiation. (B) Interaction of the radiation with achiral chromophore leads to unequal absorption, so that combination of the emerging vectors, OL and OR, leads to a resultant that describes an elliptical path as it progresses out of the plane of the paper. The ratio of the major and minor axes of the ellipse is expressed by tan 0, thus defining ellipticity. The major axis of the ellipse makes an angle (q) with the original plane, which defines the optical rotation. This figure thus demonstrates the close relation between optical rotation and circular dichroism.

For high-symmetry media like gases, liquids, cubic crystals, or uniaxial crystals with their optical axis parallel to B, and with the propagation direction of the light parallel to B, the optical eigenmodes are right- and left-handed circularly polarized waves, denoted by + and —. For such media, Eq. (1) can be simplified to [8,9]... 

A compound is considered optically active if it rotates the plane of plane-polaxized light, as described in Chapter 5. An explanation for optical activity is that, upon entering a crystal, plane-polarized light is split into two circularly polarized waves, one right-handed and the other left-handed. Since the crystal has a right-handed or left-handed character, the two circularly polarized waves travel through it with different velo-... 

According to Equation (I.S) circularly polarized light may be described by the superposition of two linearly polarized waves that are mutually orthogonal and show a phase shift of tt/2 (Figure 3.1). Conversely, linearly polarized light can be viewed as a superposition of right-handed and left-handed circularly polarized light of identical frequency and identical amplitude. 

Figure 3.1. a) Right-handed and b) left-handed circularly polarized light as a superposition of two light waves with linear polarizations that are mutually orthogonal and have a phase difference of ir/2. The path of the endpoint of the electric field vector of the circularly polarized light is drawn as a heavy line. The path of the vector endpoint of the linearly polarized light is drawn as a thin line. 

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