10,11,12 Employing focused ion beam-induced deposition techniques, helices with a smaller radius were fabricated, exhibiting a strong CD between 5 nm. 7 These helical structures and their circular dichroism can be further optimized by increasing the number of intertwined helices within the unit cell that makes up the metamaterial. demonstrated periodic gold helices exhibiting a strong CD at mid-infrared wavelengths in transmission, which were manufactured by direct laser writing followed by gold electrodeposition. Periodically arranged 3D spirals are the typical example of a chiral metamaterial in which the handedness of the helices dictates the sign of the CD. 4 Both CD and optical activity are generally pronounced in chiral metamaterials. These metamaterials can additionally exhibit a strong optical activity, which is defined as the effect of the rotation of linearly polarized light propagating through a chiral medium. This characterization requires expensive optical components, such as quarter-wave plates with minimal retardation errors over the wavelength range of interest. 4–6 The performance of these materials is often characterized based on the circular dichroism (CD), the difference in transmission of right-handed (RH) and left-handed (LH) circularly polarized light. 1–3 Many 3D chiral metamaterials have emerged as novel optical materials, e.g., efficient broadband circular polarizers at infrared and optical wavelengths. Metamaterials, various optical materials including plasmonic metasurfaces and three-dimensional (3D), structured plasmonic arrays, have recently attracted attention as they are extremely efficient in tailoring a material’s optical response and controlling the polarization of incident light. This approach is versatile, allowing to calculate the optical response in intensity and phase of any generalized chiral metamaterial upon linear, circular, or elliptical polarized illumination. A coordinate transformation then enabled the calculation of the gyro-optical response of the sample, i.e., its circular dichroism and circular polarization conversion, which is shown to be in good agreement with direct measurements. Using the advantage of symmetry considerations, all parameters of the complex Jones matrix associated with the metamaterial were determined by two linear-polarization experiments. Here, we demonstrate a new method to fully characterize any generalized chiral medium without the use of optical phase-retarding elements, such as quarter-wave plates. Efficient broadband circular polarizers can be implemented through chiral nanostructures that are periodic and possess certain spatial symmetries. Big or small to angle error with fiber axes will lead to IL~(Omega) -, IS~(Omega) + graphs towards horizontal left of right to displacement, moreover, add or reducing to fiber attenuation will bring about IL~(Omega) -, IS~(Omega) + plots along vertical up or down to shift.Due to their strong optical activity, chiral metamaterials are attractive optical elements for the control of the polarization of light. If (Omega) + or (Delta) (theta) are 0.573 degree(s), 0.181 degree(s) and 0.057 degree(s) angle off, IS values have a size of 40dB, 50dB and 50dB, respectively. While those angle error in PM fiber is increase, IL data become large, yet IS data change small. The results are shown: under ideal condition when optical fiber are non-loss and aiming, IL and IS take (Omega) + and (Omega) - as symmetrical axes, this moment, IL value is minimum, but IS value is maximum. The curves of variation of IL IS with relative angle of deviation between nonreciprocal Faraday rotator and non-magnetic rotator as well as PM fiber axes non-aim are given. Analysis of optical properties for all-fiber isolator with maintained polarization Analysis of optical properties for all-fiber isolator with maintained polarizationīy using method of Jones matrix, we analyze all-fiber isolator with polarization maintaining (PM) for optic transmission properties in this paper, the calculated formulas for insertion loss (IL) and backward isolation (IS) can be obtained.
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