The Epsilon-Near-Zero (ENZ) super-tunneling structure with weakly coupled cascaded ultra-narrow channels is proposed and demonstrated to have notably wider bandwidth than single stage tunneling structure. An extensive parametric study for such structures is performed to investigate the factors which can affect super-tunneling performance. It is found that the coupling between the ultra-narrow channels is required to be weak enough to ensure a continuous supertunneling band. In addition, electric field in the cascaded channels is enhanced, compared with that in the single channel structure.
Dennis W. Prather,
"Analysis of Epsilon-Near-Zero Metamaterial Super-Tunneling Using Cascaded Ultra-Narrow Waveguide Channels," Progress In Electromagnetics Research M,
Vol. 14, 113-121, 2010. doi:10.2528/PIERM10080205
1. Marques, R., F. Martin, and M. Sorolla, Metamaterials With Negative Parameters: Theory, Design and Microwave Applications, Wiley Series in Microwave and Optical Engineering, Wiley, New York, 2008.
2. Weng, Z. B., X. M. Wang, and Y. Song, "A directive patch antenna with arbitrary ring aperture lattice metamaterial structure," Journal of Electromagnetic Wave and Applications, Vol. 23, No. 13, 1763-1772, 2009. doi:10.1163/156939309789566879
3. Alu, A., F. Bilotti, N. Engheta, and L. Vegni, "Theory and simulations of a conformal omnidirectional sub-wavelength metamaterial leaky-wave antenna," IEEE Trans. Antennas Propag., Vol. 55, No. 6, Pt.2, 1698-1708, Jun. 2007. doi:10.1109/TAP.2007.898615
4. Pacheco, J., T. Gregorczyk, B. I. Wu, and J. A. Kong, "A wideband directive antenna using metamaterials," PIERS , 479, Honolulu, HI, Oct. 13--16, 2003.
5. Alu, A., M. G. Silveirinha, A. Salandrino, and N. Engheta, "Epsilon-near-zero metamaterials and electromagnetic sources: Tailoring the radiation phase pattern," Phys. Rev. B, Vol. 75, 155410, Apr. 11, 2007.
6. Zhou, H., Z. Pei, S. Qu, S. Zhang, J. Wang, Q. Li, and Z. Xu, "A planar zero-index metamaterial for directive emission," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 7, 953-962, 2009. doi:10.1163/156939309788355289
7. Rotman, W., "Plasma simulation by artificial dielectrics and parallel-plate media," IRE Trans. Antennas Propag., Vol. 22, 82-84, 1962. doi:10.1109/TAP.1962.1137809
8. Silveirinha, M. and N. Engheta, "Theory of supercoupling, squeezing wave energy, and field confinement in narrow channels and tight bends using epsilon near-zero metamaterials," Phys. Rev. B, Vol. 76, 245109, 2007. doi:10.1103/PhysRevB.76.245109
9. Liu, R., Q. Cheng, T. Hand, J. J. Mock, T. J. Cui, S. A. Cummer, and D. R. Smith, "Experimental demonstration of electromagnetic tunneling through an epsilon-near-zero metamaterial at microwave frequencies," Phys. Rev. Lett., Vol. 100, 023903, 2008. doi:10.1103/PhysRevLett.100.023903
10. Alu, A. and N. Engheta, "Dielectric sensing in ε-near-zero narrow waveguide channels," Phy. Rev. B, Vol. 78, 045102, Jul. 3, 2008.
12. Alu, A., M. G. Silveirinha, and N. Engheta, "Transmission-line analysis of ε-near-zero (ENZ)-filled narrow channels," Phy. Rev. E, Vol. 78, 016604, Jul. 23, 2008.
13. Alu, A. and N. Engheta, "Coaxial-to-waveguide matching with ε-near-zero ultranarrow channels and bends," IEEE Trans. Antennas Propag., Vol. 58, No. 2, 328-339, Feb. 2010. doi:10.1109/TAP.2009.2037714