Dynamic Control of Ultrathin Electromagnetic Absorber Using Active High Impedance Metasurfaces

Abstract

In recent years, active metasurfaces have induced more interests, which provides great freedom of wave manipulation and gives rise to many novel phenomena. High impedance metasurfaces are a kind of artificial structures characterized by the in-phase reflection at the resonant frequency. It works as a magnetic mirror and can be applied in subwavelength cavity, low profile reflector antenna, etc. When introduce in tunable components, it possesses versatile functionalities and broader application. In this paper, we proposed an active high impedance metasurface which exhibits highly efficient absorption to the electromagnetic incidence. As an array of diodes are loaded between the gap of periodic gratings and applied with positive bias, the absorption frequency can be dynamically controlled by the level of bias voltage. At the resonant frequency, the reflection from the metasurface can be less than 1%, implying that most of the incidence is absorbed by the magnetic resonance of high impedance metasurface. When the bias voltage is tuned from 0 to +1.33 V (the forward voltage), the resonant peak rises from 8.5 to 9.1 GHz, providing a flexible control of electromagnetic wave absorption in X band.

High-efficiency modulation of broadband polarization conversion with a reconfigurable chiral metasurface

“…The Aluminum Gallium Arsenide (AlGaAs) flip-chip PIN diodes (MA4AGP907) has a small junction capacitance of 0.025 pF, so the PIN diode can be simply modeled as a parallel RC circuit with a constant capacitance and a tunable resistance (Figure 1c). 80 The variable resistance of diode changes from infinite to 4.2Ω, while the bias voltage increases positively from 0 to +1.25 V. The diodes are divided into two pairs with opposite electric biasing for controlling the electric connection Please do not adjust margins Please do not adjust margins between the inside and outside of the annulus (Figure 1b, 1f). Then the orientation of the CSRRs on top layer can be reconfigured by precisely and continuously tuning biasing voltage on the metasurface.…”

“…1c ). 80 The variable resistance of the diodes changes from infinite to 4.2 Ω, while the bias voltage increases positively from 0 to +1.25 V. The diodes are divided into two pairs with opposite electric biasing for controlling the electric connection between the inside and outside of the annulus ( Fig. 1b and f ).…”

On-Chip Optical Beam Manipulation with an Electrically Tunable Lithium-Niobate-on-Insulator Metasurface

“…Electrically tunable devices can perform functions in several cases. Tunability enhances the control of the light on-chip, which is of great importance in photonic devices [ 17 , 18 , 19 , 20 ].…”

Design and analysis of a wideband and wide angle 3D metamaterial absorber

“…With the development of advanced detectors and precision guidance technology, controlling of electromagnetic wave radiation played vital roles in civil and military fields [1][2][3][4][5][6]. In order to avoid detected, one of the most effective approaches was to utilize the absorber which can absorb electromagnetic waves in wideband and large angles.…”

“…On the one hand, a number of evidences have proved that conventional absorbers [7][8][9] was effective to achieve wideband absorbing. 4 These authors contributed equally to this work. * Authors to whom any correspondence should be addressed.…”