optics{ global_absorption_coeff{ } }

• usage: $\mathrm{optional}$

• items: maximum 1

This group is used to specify the global absorption spectrum for the entire device.

Important

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

• 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 absorption spectra from the database or external files.

---

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{ }

• import{ } is specified in the input file.

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import_spectrum{ import_from }

• usage: $\mathrm{required}$

• type: character string

Path to a spectrum 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.

---

import_spectrum{ decadic_absorption_unit }

• usage: $\mathrm{optional}$

• type: choice

• values: yes or no

• default: no

If set to yes, then the optical absorption coefficient is assumed to be expressed in $\mathrm{dB}/\mu \mathrm{m}$.

---

constant_spectrum{ }

• usage: $\mathrm{optional}$

• items: maximum 1

Specify a constant absorption spectrum

Important

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

• Exactly one of the following must be defined: absorption_coeff, decadic_absorption_coeff within this group.

---

constant_spectrum{ absorption_coeff }

• usage: $\mathrm{optional}$

• type: real number

• values: no constraints

• unit: ${\mathrm{cm}}^{-1}$

The constant value of the absorption coefficient expressed in $1/cm$

---

constant_spectrum{ decadic_absorption_coeff }

• usage: $\mathrm{optional}$

• type: real number

• values: no constraints

• unit: $\mathrm{dB}/\mu \mathrm{m}$

The constant value of the absorption coefficient expressed in $\mathrm{dB}/\mu \mathrm{m}$

---

Examples

global_absorption_coeff{
    database_spectrum{
        name = "GaAs"
    }
}

global_absorption_coeff{
    import_spectrum{
        import_from = "filename"
        cutoff = yes  # yes/no: If yes, set values outside definition interval to zero.
                    # (default=?)
        decadic_absorption_unit = no # yes or no, default: no
    }
}

global_absorption_coeff{
    constant_spectrum{
        absorption = 0.5  # real value >= 0.0 [1/cm]
        # or
        decadic_absorption = 0.0 # real value >= 0.0
    }
}