As Inasmuch as there are no naturally existing
materials with negative , such a different category of artificial materials brings certainly many peculiar electromagnetic phenomena, different physics, and promising
applications.5–7 It is well known that in regular right-handed
materials RHMs the behaviors of electromagnetic wave
propagation are completely governed by , solely because
is always unity. From the point of view of crystal optics,
RHMs are usually classified into only three distinct categories as optically isotropic, uniaxial and biaxial. In LHMs,
however, the propagation characteristics of electromagnetic
waves are governed by both and . The appearance of
certainly makes the physical contents of the electromagnetic
wave propagations very abundant and changes the required
conditions for the above categories in LHMs.
In LH