Electronically reconfigurable metal-on-silicon metamaterial

TL;DR

This paper demonstrates a voltage-controlled, silicon-based reconfigurable metamaterial operating in the W-band, enabling dynamic control of electromagnetic wave transmission for imaging and beam-forming applications.

Contribution

It introduces a novel, electrically tunable metamaterial with integrated gold-silicon structures that modulate transmittance at high frequencies, combining device physics and wave propagation modeling.

Findings

Transmittance can be modulated by bias voltage.

Device operates effectively in the W-band (75-110 GHz).

Numerical models accurately predict device behavior.

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-{\mu}m-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.