Permeability of artificial dielectric materal

HI,

I have an artificial dielectric material structure, whose extracted relative permeability is less than 1. Real(mu) = 0.7 and imag(mu)=0.2.

I do not know how to comprehend this. What does it say about the material then?

P.S: the extracted permittivity is real = 2.7 and imag=-1.

Thanks in advance!

RZ

Are you talking about "metamaterials"? Referring to
"structure" makes me think so.

Such things tend to have "interesting" results -at a
specific wavelength corresponding to their structures-
but you shouldn't spend too much effort trying to fit the
the electromagnetic trickery's electrical result, to classical
simple dielectric behavior. Because it's neither.

Just because it measures funny, doesn't mean it's actually
a negative or an imaginary permittivity. What you've got is
an L mixed in with your C at microscale. Measure it again
at other frequencies (say, where either the L or the C of
the "cell" becomes insignificant) and your answer will be
pretty different. I've yet to see a report (not that I follow
closely) any "broadband negative permeability" or
"broadband imaginary permittivity". Tests are always at
whatever frequency makes the outcome interesting enough
to publish and off-point results mumblemumblemumble....

I agree with the above, and assume you mean at a certain frequency.

Real values smaller than 1 simply mean the the supported mode is superluminal. This happens, for example, in solid metal waveguides just above cutoff. These frequency ranges generally aren't too useful, as it's difficult to match to those modes in that region. Metamaterials with these properties are used in planar form to create leaky-wave antennas.

Nonzero imaginary parts indicate loss if positive, but if negative suggest gain -- I would assume your material parameter extraction procedure is off here.