materials are of this type: vacuum, air, glass, and plastics. Parameters: n, k (real and imaginary refractive index)

Example:

DEFINE matname= BlackGlass type=dielectric n=1.52 k=1e-3

Type metal

Nonmagnetic dispersive material which may have negative dielectric constant at the frequency of interest, which is equivalent to having n < k, e.g. metals in the infrared. Other conductive materials can be modelled as conductor type. There are two ways of specifying a metal: using the n and k values at the centre wavelength of the sources, or using a file produced FITMAT, which fits Debye and Lorentz poles to user-supplied n,k data.

Parameters: n, k , file Example:

DEFINE matname= Gold3_1um type=metal n=0.3 k=11.23 DEFINE matname= Nickel type=metal file=nickel.poles

Type conductor

Normal conductor, with ε = ε0+jσ/ω Useful for metal waveguide boundaries, at frequencies where the normal conduction model applies (below about 1 THz). In optical simulations, ordinary conductors are primarily useful in simulating loads.

Parameters: conductivity (in units of (Ωm)-1)

Example:

DEFINE matname=copper type=conductor conductivity=5.8e7

Type magnetic

Magnetic material, whose properties are specified by

complex µ and ε, specified in SI units, not the relative µ and ε.

Parameters: epsReal epsImag muReal muImag

Example:

DEFINE name=ferrite type=magnetic epsReal=18, epsImag=0 muReal=220 muImag=1.1

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IBM Release 1.93 manual Parameters epsReal epsImag muReal muImag