Ferrite-based magnetically tunable left-handed metamaterial composed of SRRs and wires

Abstract

We experimentally demonstrate a magnetically tunable left-handed metamaterial by introducing yttrium iron garnet rods into SRRs/wires array. It shows that the left-handed passband of the metamaterial can be continuously and reversibly adjusted by external dc applied magnetic fields. Retrieved effective parameters based on simulated scattering parameters show that tunable effective refraction index can be conveniently realized in a broad frequency range by changing the applied magnetic field. Different from those tuned by controlling the capacitance of equivalent LC circuit of SRR, this metamaterial is based on a mechanism of magnetically tuning the inductance via the active ambient effective permeability.

Tunable Single-Negative Metamaterials Based on Microstrip Transmission Line With Varactor Diodes Loading

“…In recent years, tunable metamaterials have attracted intensive attentions due to their particular applications in optical switching, nonlinear modulation, and so on [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59]. The common mechanism is to introduce certain controllable materials or lumped elements into the metamaterial units.…”

“…The common mechanism is to introduce certain controllable materials or lumped elements into the metamaterial units. For example, in [42][43][44][45][46][47][48] ferroelectric materials, ferromagnetic materials and liquid crystals are hired. In [49] and [50], the authors also show employing photosensitive semiconductor in the split ring resonators or electric-field-coupled inductor-capacitor resonators can make them become tunable.…”

Microwave Switch based on Tunable Single Negative Metamaterials

“…For example, in Ref. [9][10][11][12][13][14][15] ferroelectric materials, ferromagnetic materials, and liquid crystals are hired. These metamaterials can be controlled by dynamic magnetic fields, high voltages or temperature.…”

Magnetically Tunable Ferrite-Dielectric Left-Handed Metamaterial

“…He et al used yttrium iron garnet (YIG) sheets and copper wires to make tunable refractive index metamaterial [9]. Kang et al applied YIG rods with SRRs/wires to display a tunable double-negative metamaterial [10]. The electrically tunable metamaterials can use ferroelectric to offer tunable dielectric permittivity by bias electric field [11].…”