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Chiral metamaterial-based sensor is designed for sensing the change in substance ratio of chemical substances when combined with distilled water. These samples have been prepared with 10%, 50% and 90% volume fraction of methanol, ethanol, acetone, ammonia and isopropyl alcohol. The complex permittivity of the prepared samples has been measured by Agilent 85070E dielectric probe kit and compared with the simulations. In the proposed design, linear shifts with the frequency bands of more than 100 MHz are observed in different measurements. For different material sensing, pure samples have been used and their reflection coefficient measurement results have been presented. Unique side of this study is that the structure provides very clear and sensitive results and presents a new approach to the microfluidic sensor applications by using the sample holder.

We bring to light an electroweak model which has been reappearing in the literature under various guises.${}^{1-5}$ In this model, weak isospin is shown to act automatically on states of only a single chirality (left). This is achieved by building the model exclusively from the raising and lowering operators of the Clifford algebra $ℂl(4)$. That is, states constructed from these ladder operators mimic the behaviour of left- and right-handed electrons and neutrinos under unitary ladder operator symmetry. This ladder operator symmetry is found to be generated uniquely by $su{(2)}_L$ and $u{(1)}_Y$. Crucially, the model demonstrates how parity can be maximally violated, without the usual step of introducing extra gauge and extra Higgs bosons, or ad hoc projectors.

A novel bis-palladium(II) complex of doubly N-confused octaphyrin (Pd${}_2$-2) adopting a Möbius-twisted topological structure was synthesized and characterized. Due to the effective 36$\pi$-electronic delocalization over the Möbius-twisted octaphyrin scaffold, characteristic Soret and Q-like absorption features were observed in the near-infrared (NIR) region. However, the complex Pd${}_2$-2 exhibited weak aromatic character attributed to the distinct cross-conjugated resonance contribution as inferred from the ¹H NMR chemical shifts as well as theoretical assessments ($e.g.$ nucleus-independent chemical shift (NICS)). Since the bis-palladium(II) complexation of doubly N-confused octaphyrin 2 imparted significant conformational stability, topologically chiral enantiomers of Pd${}_2$-2 were successfully separated as ($P)$- and ($M)$-twisted forms. The resulting isomers revealed relatively large circular dichroism (CD) responses with an absorption anisotropy factor of $g_{abs}$$=$ 0.009 in the NIR region ($\lambda =$ 823 nm). In addition, the cyclic voltammogram of Pd${}_2$-2 revealed redox-rich properties due to its large $\pi$-conjugated system.

We investigated chirality transfer processes with two amide-linked zinc bisporphyrinates as hosts and chiral amino acid esters as guests. The linkers in these hosts contain a coordination site (pyridyl nitrogen or amino nitrogen). CD spectra were measured after titration of these zinc bisporphyrinates with amino acid esters. The CD spectra show that the signals were inverted during the titration. This result suggests that there is a two-step chirality induction process, which is most likely dominated by the corresponding 1:1 and 1:2 host-guest complexes. In the 1:1 complexes, the pyridyl nitrogen or amino nitrogen in the linkers is coordinated with zinc. NMR spectra confirmed such coordination interactions. Theoretical calculations also confirmed the corresponding chirality induction and inversion. This work provides a useful strategy to tune chirality transfer processes by introducing an extra coordination site in the linker.

In this study, a dynamic chiral metamaterial (MTM) structure leading to an asymmetric electromagnetic (EM) wave transmission for linear polarization is presented. The structure is composed of square-shaped resonator with gaps on both sides of a dielectric substrate with a certain degree of rotation. The dynamic structure is adjustable via various parameters to fit any desired frequency ranges. Theoretical and experimental analysis of the proposed structure are conducted and given in detail. The suggested model can provide constant chirality over a certain frequency band and thus, it can be used to design myriad novel devices such as EM transmission and antireflection filters, and polarization rotators for desired frequency regimes.

Chiral metamaterial (MTM) researchers generally concentrate and aim to obtain large chirality with optical activity in certain frequencies. However, new generation planar chiral MTM which have small and constant/flat chirality over a certain frequency band have not queried by this time in literature. In fact, this area is mostly ignored by researchers. This study, first one according to best of our knowledge in the literature, is investigating the small and constant/fixed chirality and focuses on the new generation planar chiral MTM based on circular split ring resonators (SRRs), in details. It can be seen from the results that the proposed model can provide small and constant/flat chirality over a certain frequency band and thus it can be used to design myriad novel devices such as polarization rotators, and electromagnetic transmission and antireflection filters for several frequency regions.

As a historical remark the similarities are pointed out between a form of chiral action introduced by Schwinger and the formalism used in the noncommutative extensions of electromagnetism.