optics{ global_refractive_index{ } }

• usage: $\mathrm{optional}$

• items: maximum 1

This group is used to specify the effective refractive index $n_{\mathrm{eff}}(\lambda )$ of the modelled device.

Important

The following general conditions must be satisfied when defining optics{ global_refractive_index{ } }

• Exactly one of the following must be defined: database_spectrum{ }, import_spectrum{ }, constant_spectrum{ } within this group.

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Maintained Keywords

The keywords below are available in at least one of currently published releases and are planned to be included also in the next release.

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database_spectrum{ }

• usage: $\mathrm{optional}$

• items: maximum 1

Importing the spectrum from the database or external files.

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database_spectrum{ name }

• usage: $\mathrm{required}$

• type: character string

Name of the spectrum contained in the database.

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import_spectrum{ }

• usage: $\mathrm{optional}$

• items: maximum 1

Importing spectrum from a file

Important

The following general conditions must be satisfied when defining import_spectrum{ }

• The global group import{ } is specified in the input file.

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import_spectrum{ import_n_from }

• usage: $\mathrm{required}$

• type: character string

Path to a spectrum of the real part of the refractive index for importing

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import_spectrum{ import_k_from }

• usage: $\mathrm{optional}$

• type: character string

Path to a spectrum of the imaginary part of the refractive index for importing

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import_spectrum{ cutoff }

• usage: $\mathrm{required}$

• type: choice

• values: yes or no

If set to yes, then the values of the spectrum which are outside the definition interval are set to zero. Otherwise, the spectrum is extrapolated as a constant with the value on the boundary of the imported data.

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import_spectrum{ energy_spectrum }

• usage: $\mathrm{optional}$

• type: choice

• values: yes or no

• default: no

If set to yes, then the imported spectrum is assumed to be given as a function of energy. Otherwise, the spectrum is assumed to be given as a function of wavelength.

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constant_spectrum{ }

• usage: $\mathrm{optional}$

• items: maximum 1

Specify a constant refractive index spectrum

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constant_spectrum{ n }

• usage: $\mathrm{required}$

• type: real number

• values: (0.0, ...)

• unit: $-$

• default: $r=1.0$

Constant value of the real part of the refractive index.

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constant_spectrum{ k }

• usage: $\mathrm{optional}$

• type: real number

• values: no constraints

• unit: $-$

• default: $r=0.0$

Constant value of the imaginary part of the refractive index.

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compute_absorption_coeff{ }

• usage: $\mathrm{required}$

• items: maximum 1

When defined, then calculates absorption coefficient from imaginary part of the reflective index.