# Passive fiber¶

class PassiveFiber(length=0, core_radius=0, background_loss=0, core_na=0)

PassiveFiber describes a step-index single-mode fiber with no dopant ions. It extends the FiberBase class by stating that there is no emission or absorption by ions. The only possible gain comes of stimulated Raman scattering.

__init__(length=0, core_radius=0, background_loss=0, core_na=0)
Parameters: length (float) – Fiber length core_radius (float) – Core radius background_loss (float) – Linear loss of the core (1/m, NOT in dB/m) core_na (float) – Numerical aperture of the core
get_channel_emission_cross_section(freq, frequency_bandwidth)

Passive fiber has no gain.

get_channel_absorption_cross_section(freq, frequency_bandwidth)

Passive fiber has no absorption by dopant ions.

core_area()

Returns the core area of the fiber defined as pi*r**2, where r is the core radius.

Returns: Core area float
nonlinear_effective_area(freq)

Returns the nonlinear effective area of the fundamental fiber mode with the given frequency. The method used is determined by the attribute self.effective_area_type.

Parameters: freq (float or numpy float array) – The frequency of the optical signal (Hz). The nonlinear effective area Same as argument type.