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We present optical slot antennas and their applications to photonic devices. We show that metallic nanoslots have the properties of a slot antenna by measuring the transmission spectra and far-field radiation patterns and then prove that they can be physically regarded as magnetic dipoles in the optical region. Additionally, we can generate directional radiations from optical slot antennas by adopting the geometry of radiofrequency Yagi-Uda antenna and properly adding auxiliary elements called reflectors and directors to a single slot antenna. We present two cases as the applications of optical slot antennas. One is the integration of slot antennas to plasmonic waveguides. This combination can be used as a basic unit for optical interconnection to free space and plasmonic via in multilayered plasmonic structures. The other is the integration of slot antennas to the electrode of light-emitting diodes (LEDs). Using slot antennas, we can control the polarization and direction of emissions from LEDs. Besides the above-mentioned two cases, we expect that optical slot antennas have possible applications to various photonic devices and can be essential elements in future integrated photonic circuits with nanometer scales.

The simplest sodide, LiNa(CH3NH2)n, is obtained with equimolar mixtures of lithium and sodium in methylamine. Using differential thermal analysis, the sodide's phase diagram is obtained and then presented as a function of N. Alkali metal nuclear magnetic resonance and electron paramagnetic resonance spectroscopy are performed to determine the occurrence of an electronically conducting liquid phase with near-metallic character. Results indicate that the liquid LiNa(CH3NH2)4 has a conductivity comparable to that of the near metal Li(CH3NH2)4.

Differential thermal analysis facilitates the analysis of phase equilibria and compound formation in lithium-ethylamine and lithium-sodium ethylamine systems. EPR analysis shows the absence of metallic characters in solid and solution states. Magnetic susceptibilities exhibit the diamagnetic nature of these deep blue-black systems. NMR analysis shows the presence of Li+ and Na- in solid and liquid phases.

Ni‐rich layered oxide cathodes are an immediately applicable alternative for meeting the high energy density demand of lithium‐ion batteries. The most significant hurdle of Ni‐rich layered cathode materials is their poor cyclability because of their increasing surface resistance due to their electrochemically reactive surfaces causing side reactions and the occurrence of Li/Ni cation mixing. Surface coating has been extensively studied for safeguarding particles, thereby leading to increases in electrochemical performance; however, the synthesis conditions must be carefully controlled due to the fragile surface of a Ni‐rich layered cathode. Herein, an effective coating method with self‐assembled ZrO2 (SA–ZrO2) on the surface of a Ni‐rich layered cathode material, LiNi0.82Co0.09Mn0.09O2 (NCM82), through a low‐temperature self‐combustion reaction is proposed. SA–ZrO2 is built by a combustion reaction of Zr(SO4)2·4H2O and thioacetamide to improve the surface stability of the cathode. In addition, a very small content of SOx is retained from the precursor, which promotes high lithium diffusion on the surface. Systematic analyses by X‐ray photoelectron spectroscopy and transmission electron microscopy demonstrate that this highly homogeneous ZrO2 coating layer, which is prepared at a low temperature of 500 °C, largely enhances the electrochemical performance in the half‐cell and full‐cell. [ABSTRACT FROM AUTHOR]

[Cs+(Cryptand[2.2.2])]I− (1; Cryptand[2.2.2] = C222) was characterized via single‐crystal X‐ray diffraction and was shown to crystallize in the monoclinic space group I2/c system with a = 8.9605 (2), b = 23.5073 (5), c = 11.7563 (3) Å, and β = 93.792 (2)°. Stationary and magic angle spinning (MAS) experiments under different magnetic fields allowed for the separation of the chemical shift and quadrupole coupling tensor parameters. Remarkably, MAS spectra showing pure second‐order quadrupole powder patterns at 4.23 T were observed for 133Cs nuclei with small quadrupole moments owing to the large electric field gradients (EFGs) caused by short CsO and CsN bond distances in the [Cs+(C222)] ions. Stationary NMR powder patterns with a combination of the chemical shifts and second‐order quadrupolar interactions were observed. The EFG and chemical shift tensor components calculated using the atomic coordinate files and Gaussian 09 were reasonably consistent with the experimental values. [ABSTRACT FROM AUTHOR]