TY - JOUR
T1 - Terahertz epsilon-near-zero graded-index lens
AU - Torres, Víctor
AU - Pacheco-Peña, Víctor
AU - Rodríguez-Ulibarri, Pablo
AU - Navarro-Cia, Miguel
AU - Beruete, Miguel
AU - Sorolla, Mario
AU - Engheta, Nader
PY - 2013/4/8
Y1 - 2013/4/8
N2 - An epsilon-near-zero graded-index converging lens with planar faces is proposed and analyzed. Each perfectly-electric conducting (PEC) waveguide comprising the lens operates slightly above its cut-off frequency and has the same length but different cross-sectional dimensions. This allows controlling individually the propagation constant and the normalized characteristic impedance of each waveguide for the desired phase front at the lens output while Fresnel reflection losses are minimized. A complete theoretical analysis based on the waveguide theory and Fermat's principle is provided. This is complemented with numerical simulation results of two-dimensional and three-dimensional lenses, made of PEC and aluminum, respectively, and working in the terahertz regime, which show good agreement with the analytical work.
AB - An epsilon-near-zero graded-index converging lens with planar faces is proposed and analyzed. Each perfectly-electric conducting (PEC) waveguide comprising the lens operates slightly above its cut-off frequency and has the same length but different cross-sectional dimensions. This allows controlling individually the propagation constant and the normalized characteristic impedance of each waveguide for the desired phase front at the lens output while Fresnel reflection losses are minimized. A complete theoretical analysis based on the waveguide theory and Fermat's principle is provided. This is complemented with numerical simulation results of two-dimensional and three-dimensional lenses, made of PEC and aluminum, respectively, and working in the terahertz regime, which show good agreement with the analytical work.
UR - http://www.scopus.com/inward/record.url?scp=84875981975&partnerID=8YFLogxK
U2 - 10.1364/OE.21.009156
DO - 10.1364/OE.21.009156
M3 - Article
C2 - 23572004
AN - SCOPUS:84875981975
SN - 1094-4087
VL - 21
SP - 9156
EP - 9166
JO - Optics Express
JF - Optics Express
IS - 7
ER -