Electronically reconfigurable metal-on-silicon metamaterial

Abstract

Reconfigurable metamaterial-based apertures can play a unique role in both imaging and in beam-forming applications, where current technology relies mostly on the fabrication and integration of large detector or antenna arrays. Here, we report the experimental demonstration of a voltage-controlled, silicon-based electromagnetic metamaterial operating in the W-band (75-110 GHz). In this composite semiconductor metamaterial, patterned gold metamaterial elements serve both to manage electromagnetic wave propagation while simultaneously acting as electrical Schottky contacts that control the local conductivity of the semiconductor substrate. The active device layers consist of a patterned metal on a 2-μm-thick n-doped silicon layer, adhesively bonded to a transparent Pyrex wafer. The transmittance of the composite metamaterial can be modulated over a given frequency band as a function of bias voltage. We demonstrate a quantitative understanding of the composite device through the application of numerical approaches that simultaneously treat the semiconductor junction physics as well as wave propagation.

Controlling phase of microwaves with active graphene surfaces

“…The bottle-neck of this challenge is originated from the lack of an active material for long wavelengths. To overcome this challenge, metamaterials integrated with MEMS 6,7 , semiconductors 8,9 and diodes [10][11][12] have been used to control amplitude and phase of terahertz and microwaves. Recent developments in the field of 2-dimentional (2D) materials provide a new perspective for active control of light in a very broad spectrum.…”

Dynamic electromagnetic metamaterials

“…Several other methods have been utilized to overcome the lack of commercially available lumped element components and have achieved frequency, amplitude and phase modulation. One particularly intriguing method involves the integration of metamaterials with semiconductors [14,17,18,23,24,29,[33][34][35][36]38]. Although it is straightforward to fabricate metamaterial/semiconductor structures within a typical university clean room setting, one study realized ETMs through fabrication directly within the semiconductor foundry process itself [29].…”

MEMS for Plasmon Control of Optical Metamaterials

“…Active optical control by metamaterials, enabling tuning, modulating, and switching at resonant wavelengths, has recently attracted attention [32]- [34]. To realize this goal, studies on tunable metamaterials have been carried out using various methods including electrical controls utilizing semiconductors [35]- [40], magnetostatic control [41], optical controls [42]- [45], phase-change media [46]- [49], liquid crystals [50], [51], and mechanical controls utilizing micro electromechanical systems (MEMS) [52]- [61]. Active optical devices having unprecedented optical characteristics have been realized by using tunable metamaterials.…”