Transmission control by asymmetric electromagnetically induced transparency-like metamaterials in transverse electromagnetic waveguide

• Published in: Physics letters. A 2019-12, Vol.383 (35), p.126000, Article 126000
• Main Authors: Bagci, Fulya, Akaoglu, Baris
• Format: Article
• Language: English
• Subjects: Electromagnetically induced transparency; Metamaterial; Modulation ratio; Radiative resonance; Surface current distributions
• ISSN: 0375-9601; 1873-2429
• DOI: 10.1016/j.physleta.2019.126000

•Removal of degeneracy via asymmetry is experimentally demonstrated with an electromagnetically induced transparency-like metamaterial.•Bandwidth and transparency are modulated in a TEM waveguide.•A modulation ratio of 29.5 dB in transmission is experimentally demonstrated by only increasing the voltage 4 volts.•Resonances are explained by surface current distribution analyses. We numerically and experimentally present passive and active electromagnetically induced transparency-like metamaterials in a TEM waveguide under normal excitation. Asymmetry of the metamaterial unit cell leads to the splitting of the radiative resonance. Surface current distributions are analyzed to account for each resonance. Moreover, by implementing a varactor diode to one of the gaps of the double-split ring resonator, electromagnetically induced transmission-like band is shifted in frequency and the corresponding bandwidth is modulated. A modulation ratio of 29.5 dB in transmission is experimentally demonstrated by only increasing the bias voltage 4 volts.