Abstract-The Goos-Hächen (GH) shift at the surface of chiral negative refractive media is analyzed theoretically. GH shifts are observed for both perpendicular and parallel components of the reflected field near the respective critical angles. It is found that positive and negative shifts can be attained when the incident angle is larger than the first critical angle, whereas if the angle of incidence exceeds the second critical angle, only positive shifts can be observed. In addition, a Gaussian beam is further adopted to illustrate the effect of the GH shifts.

Abstract-Microstrip patch antennas have several advantages over conventional antennas including their low profile structure, light weight and low cost. As such, they have been widely used in a variety of applications. However, one of the major drawbacks of this antenna is the low bandwidth. In this paper, bandwidth of a dual patch antenna is improved by etching dummy EBG pattern on the feedline. Effects of different positions of the feedline on the bandwidth are also studied. A good improvement in bandwidth for the antenna with the dummy EBG pattern when compared to the reference antenna is obtained for all the feedline positions.

Exceptional points are spectral singularities in non-Hermitian systems at which two or more eigenvalues and their corresponding eigenvectors simultaneously coalesce. Originating from quantum theory, exceptional points have attracted significant attention in optics and photonics because their emergence in systems with nonconservative gain and loss elements can give rise to many counterintuitive phenomena. Metasurfaces -two-dimensional artificial electromagnetic materials structured at the subwavelength scale -can provide a versatile platform for exploring such non-Hermitian phenomena through the addition of dissipation and amplification within their unit cells. These concepts enable a wide range of exotic phenomena, including unidirectional propagation, adiabatic mode conversion, and ultrasensitive measurements, which can be harnessed for technological applications. In this article, we review the recent advances in exceptional-point and non-Hermitian metasurfaces. We introduce the basic theory of exceptional point and non-Hermiticity in metasurfaces, highlight important achievements and applications, and discuss the future opportunities of non-Hermitian metasurfaces from basic science to emerging technologies.