![]() Hence, strictly speaking, they are intrinsically achiral in three dimensions. ![]() Asymmetric propagation of circularly polarized waves is achieved using structures so-called planar chiral metamaterials that preserve symmetry along the direction of light propagation. A large variety of CMMs structure unit cells were investigated that evoke a huge AT effect that firstly was obtained for circularly polarized waves with various designs of CMMs including conjugated gammadions, split-ring structure, cut-wire structure, three-dimensional helix structure, L-shaped structure, omega-shaped particles and other novel structures. Many polarization devices based on CMMs have been designed and reported, such as rotators, circular polarizers, and polarized converters. CMMs can be designed to exhibit properties such as giant circular dichroism, optical activity and AT effect, which offer more possibilities for flexible control of electromagnetic waves. A CMM structure does exhibit any mirror symmetry and its mirror image cannot be superimposed on itself by any planar manipulation. After systematically reviewing the research history of the AT effect, we found that chirality plays a crucial role in realizing the AT effect.Ĭhiral metamaterials (CMMs) are a subclassification of metamaterials, which have attracted the attention of many scholars since they were proposed by Pendry et al. In contrast to the non-reciprocal transmission, the diode-like AT effect is reciprocal and fully satisfies Lorentz reciprocity theorem. The new effect in some ways resembles the famous non-reciprocity of the Faraday effect in magneto-optic materials and nonlinear media but requires no magnetic field for its observation. This effect is a polarization sensitive transmission effect asymmetric with respect to the direction of wave propagation. Recently, it was found that metamaterials with strong symmetry breaking can exhibit the propagation direction-dependent polarization sensitive transmission effect, known as asymmetric transmission (AT), for both circular and linear polarizations. We will only deal with the LP, QWR and M, and it is denoted in Tt.Metamaterials, as a kind of composite materials composed of subwavelength scale composites, have been widely studied in recent years because of their unique electromagnetic properties, such as negative refraction, polarization conversion, invisibility cloak. In this problem, we do not care with the input wave. In short, we will have a complete mathematical equation as follows, This matrix has several definition for different optical component. So, each optical component is described by matrix called “Jones matrix”. LP, QWR and M are standing for linear polarizer, quantum wave retarder and mirror, respectively. But in this problem, I put them in with the description explained. ![]() The scheme for this system, mostly based on Faraday rotator. Obviously, the source will get damaged when they received any signal back to the local system. So, this device is used in combination with laser in order to prevent back reflection to the source (laser). But in reality, it does not and works totally different. Physically, it similar with the fiber optic. So, I found out like this, Optical isolator ( ) What is it? How does it work? How does the scheme look like? How does the device physically representated? The first step I do when I get the problem is, asking to myself: Umm. Show that isolation of the light reflected by a planar mirror may be achieved by using a combination of a linear polarizer and a quarter-wave retarder with axes 45° with respect to the transmission axis of the polarizer. Recently, I get an interesting problem from one of my course,Īn optical isolator transmits light travelling in one direction and blocks it in the opposite direction. One of the reason why I do like study engineering course especially photonics is the application of the mathematical modelling in making/proofing/calculating or even inventing something that has not even invented before, and now it has become a reality, being used widely in the world.
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