Optical properties of an ideal homogeneous causal left-handed material slab.
The optical properties of a homogeneous slab of material characterized by causal permittivity epsilon (f) , and permeability mu (f) are investigated through finite difference time domain simulations. Lorentzian epsilon (f) and mu (f) are used to produce values of interest in the resulting index n (f) , namely, n<0 , 0<n<1 , and n approximately 0 . Negative refraction of both cw and pulsed waves is observed when operated in the left-handed medium (LHM) regime. In particular, we examined materials having both an impedance matched to free space and an impedance not matched to free space, as is the case of a split-ring resonator structure, and find it to exhibit LHM behavior, in agreement with previously published claims. Spherical aberration and channeling are observed as the magnitude of the negative index is increased beyond -1 . Critical angle phenomena are seen for indices in the range 0<n<1 , and a spatial filter effect is identified in the n approximately 0 region. A transmission bandpass in the vicinity of n approximately 0 is identified as a "ferromagnetic antiresonance," where the material acts as both a frequency and a spatial filter.
Loschialpo
P F
PF
Naval Research Laboratory, Washington, D.C. 20375, USA.
Forester
D W
DW
Smith
D L
DL
Rachford
F J
FJ
Monzon
C
C