One-Plane Glide-Symmetric Holey Structures for Stop-Band and Refraction Index Reconfiguration

Abstract

This work presents a new configuration to create glide-symmetric structures in a single plane, which facilitates fabrication and avoids alignment problems in the assembly process compared to traditional glide-symmetric structures based on several planes. The proposed structures can be printed on the metal face of a dielectric substrate, which acts as a support. The article includes a parametric study based on dispersion diagrams on the appearance of stop-bands and phase-shifting by breaking the symmetry. In addition, a procedure to regenerate symmetry is proposed that may be useful for reconfigurable devices. Finally, the measured and simulated S parameters of 10 × 10 unit-cell structures are presented to illustrate the attenuation in these stop-bands and the refractive index of the propagation modes. The attenuation obtained is greater than 30 dB in the stop-band for the symmetry-broken prototype.

Wave Propagation in Periodic Metallic Structures with Equilateral Triangular Holes

“…A bandgap study of the mirror-and glide-symmetric periodic structures when varying the size of the hole (the triangle side e) and the period d of the unit cell is shown in Figure 11. The glide-symmetric configuration offers a wider bandwidth compared to the mirror-symmetric one, as also pointed out by previous studies on holey structures with circular [9] and elliptical [31] holes. Furthermore, the relative bandgap increases as the period of the unit cell is larger.…”

“…A similar behavior is also observed for the glide-symmetric configuration but considering now the second and third modes. Unlike what found for triangular holes, in the case of circular and elliptical holes [9,31], there is an optimum ratio between the size of the hole and the period at which the bandgap is maximum. Beyond that ratio, the relative bandgap starts to decay.…”

On the Benefits of Glide Symmetries for Microwave Devices

“…Furthermore, glide symmetry has also been employed for filtering purposes in planar technology [57], [87]. For example, in [45] glide-symmetric mushrooms demonstrated to provide a wider rejection bandwidth than conventional ones.…”

Periodic Structures With Higher Symmetries: Their Applications in Electromagnetic Devices

“…Similarly, glide symmetry was employed in planar bifilar technology to control the stopbands generated by creating or breaking this symmetry [48]. In [49], elliptical holes between two dielectric layers were proposed to produce stopbands by breaking the glide symmetry.…”

“…Although the majority of the examples of glide symmetry use two layers to implement the symmetry, a new type of flat glide symmetry was proposed in [49]. In this work, elliptical holes were introduced between two dielectric layers.…”