finesse.gaussian.BeamParam.w0

property BeamParam.w0

The radius of the waist, \(w_0\), of the beam, in metres.

Computed as,

\[w_0 = \sqrt{\frac{z_R \lambda}{n_r \pi}},\]

where \(z_R\) is the Rayleigh range (given by BeamParam.zr, or BeamParam.imag), \(\lambda\) is the beam wavelength (given by BeamParam.wavelength) and \(n_r\) is the refractive index of the associated medium (given by BeamParam.nr).

Getter:

Returns the beam waist-size.

Setter:

Sets the beam waist-size.