Title : 
Broadband Switching Nonlinear Metamaterial
         
        
            Author : 
Wall, Walter S. ; Rudolph, Scott M. ; Hong, Sun K. ; Morgan, Kenneth L.
         
        
            Author_Institution : 
US Naval Res. Lab., Washington, DC, USA
         
        
        
        
        
        
        
            Abstract : 
In this letter, we present a nonlinear metamaterial capable of transitioning between a broadband reflective and broadband nonreflective state depending on the incident power level. Below the activation voltage, broadband reflectivity is created by forbidding propagation through the metamaterial as a result of the effective permittivity and permeability having different signs. Above the activation voltage, reflection is suppressed by matching the effective permittivity and permeability. Full-wave simulations are performed to analyze the electromagnetic characteristics of the structure, with experimental results presented at S-band frequencies in a WR-284 waveguide. These measurements demonstrate a 10 dB reduction in reflected amplitude over an 18% bandwidth, a 3-dB reduction over a greater than 30% bandwidth, and a maximum difference in reflection of nearly 42 dB.
         
        
            Keywords : 
electromagnetic metamaterials; electromagnetic wave propagation; electromagnetic wave reflection; magnetic permeability; permittivity; waveguides; S-band frequency; WR-284 waveguide; activation voltage; broadband nonreflective state; broadband reflective state; broadband switching nonlinear metamaterial; electromagnetic characteristics; full-wave simulation; gain 10 dB; gain 3 dB; incident power level; permeability; permittivity; Bandwidth; Broadband antennas; Broadband communication; Magnetic materials; Magnetic resonance imaging; Metamaterials; Reflection; Diodes; metamaterials; nonlinear magnetics;
         
        
        
            Journal_Title : 
Antennas and Wireless Propagation Letters, IEEE
         
        
        
        
        
            DOI : 
10.1109/LAWP.2014.2308989