finesse.components.cavity.Cavity
¶
Overview
- class finesse.components.cavity.Cavity(name, *args, **kwargs)[source]¶
Bases:
TraceDependency
Represents a cavity in an interferometer configuration.
This class stores the shortest path between the start node and end node of the cavity and holds symbolic expressions for each physical attribute of the cavity. Numeric values corresponding to these attributes are obtained through the relevant properties.
Adding a Cavity to a
Model
results in the beam parameters of all nodes in the cavity path being set according to the cavity eigenmode (Cavity.q
) when a beam trace is performed (e.g. at the start of a modal based simulation). The mode of the cavity is then also used as a trace starting point when setting beam parameters at nodes outside of the cavity - see Tracing the beam for details on the beam tracing algorithm.- Parameters
- namestr
Name of newly created cavity.
- source
OpticalNode
orPort
Node / Port that the cavity path starts from. If no via node is specified, then the cavity path will be given by the shortest path from source back to the component that owns source.
If a port is given then the output optical node of that port will be used as the source.
- via
OpticalNode
, optional Node that the cavity path must traverse via; defaults to None.
Note that, unlike source, this cannot be a
Port
object as this would be ambiguous for beamsplitter type components - i.e. determination of which node to use cannot be assumed automatically.- prioritynumber, optional; default: 0
Priority value for beam tracing. Beam tracing dependencies are sorted in descending order of priority - i.e. higher priority value dependencies will be traced first. Any dependency with a priority value of zero will be traced, after non-zero priority dependencies, in alphabetic order of the dependency names.
Properties
The round-trip ABCD matrix of the cavity in both plannes. |
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The tangential round-trip ABCD matrix of the cavity. |
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The sagittal round-trip ABCD matrix of the cavity. |
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The free-spectral-range (FSR) of the cavity. |
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The cavity full-width-half-maximum (FWHM). |
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The resolution of the cavity in both planes. |
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The resolution of cavity in the tangential plane. |
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The resolution of cavity in the sagittal plane. |
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The finesse of the cavity. |
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The stability of the cavity, in both planes, given by the \(g\)-factor: |
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The accumulated round-trip Gouy phase of the cavity in both planes (in degrees). |
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The round-trip Gouy phase in the tangential plane (in degrees). |
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The round-trip Gouy phase in the sagittal plane (in degrees). |
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The stability, g, of the cavity in the tangential plane. |
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The stability, g, of the cavity in the sagittal plane. |
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Flag indicating whether any geometric parameter inside the cavity is changing. |
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Flag indicating whether the cavity is critically stable. |
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Flag indicating whether the cavity is critically stable in the tangential plane. |
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Flag indicating whether the cavity is critically stable in the sagittal plane. |
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Flag indicating whether the cavity is a Fabry-Perot cavity. |
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Flag indicating whether the cavity is stable. |
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Flag indicating whether cavity is stable in the tangential plane. |
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Flag indicating whether cavity is stable in the sagittal plane. |
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The round-trip loss of the cavity as a fraction of the incoming power. |
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The stability of the cavity, in both planes, given by the \(m\)-factor: |
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The mode separation frequency of the cavity in both planes. |
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The mode separation frequency in the tangential plane. |
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The mode separation frequency in the sagittal plane. |
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The stability, m, of the cavity in the tangential plane. |
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The stability, m, of the cavity in the sagittal plane. |
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The |
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The pole-frequency of the cavity. |
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The eigenmode of the cavity in both planes. |
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The eigenmode of the cavity in the tangential plane. |
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The eigenmode of the cavity in the sagittal plane. |
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The round-trip optical path length of the cavity (in metres). |
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Starting node of the cavity. |
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The cavity storage time (\(\tau\)). |
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Via node of the cavity. |
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The waist size of the cavity in both planes. |
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The waist size of the cavity in the tangential plane. |
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The waist size of the cavity in the sagittal plane. |
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The position of the cavity waist in both planes. |
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The waist position of the cavity in the tangential plane. |
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The waist position of the cavity in the sagittal plane. |
Methods
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Determines whether any parameter of any component inside the cavity is changing. |
A string representation of the cavity route. |
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Generates a string representation of the cavity round-trip ABCD matrix operations. |
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Obtains a dictionary of source: target mappings where source -> target and target is an exit node of the cavity. |
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Initialises the symbolic equations of the cavity and calculates the cavity path from the associated model. |
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Plots the beam representing the cavity eigenmode over the path of the cavity. |
Traces the cavity eigenmode through the cavity path. |