  Hyperbolic Metamaterials, as a non-magnetic anisotropic artificial structure,
show metal properties in one direction and dielectric behavior in orthogonal
directions. The proposed hyperbolic metamaterial filter in this project is
designed with the metal wire mesh perpendicular to the alternative layers of
dielectric materials, keeps TM center wavelength unchanged for the different
angle of incident light in MDIR regime. The geometric size of this
nanostructure is smaller than the working wavelength and supports big
wavevectors due to hyperbolic dispersion. In contrast with conventional Bragg
stack, the copper fakir bed makes the transmission properties of the filter the
same. For this purpose, the state-of-the-art fabrication methods are required
to make such small dimensions in alternative layers of amorphous silicon and
silicon dioxide. In this work, first we demonstrate the simulation of Bragg
stack with RCWA and finite element methods. Then we focus on our first-time
multistep lithography method used to fabricate the filter. Finally, we
experimentally verify the optical characteristic of the fabricated filter using
Fourier-transform infrared spectroscopy. The experimental and spectrometry data
shows that transmission properties of the hyperbolic metamaterial filter remain
the same for oblique TM polarized incident light.
