What are the normalized Stokes parameters?

In this article, we will teach you What are the normalized Stokes parameters?

What are the normalized Stokes parameters?

The normalized Stokes parameters are a set of four parameters used to describe the polarization state of electromagnetic waves. They provide a complete representation of the polarization characteristics of light or radio waves. The normalized Stokes parameters are defined as:

the normalized Stokes parameters

The stokes parameter S0S_0S0: Also known as the total intensity parameter, S0S_0S0 represents the total power of the wave, regardless of its polarization state.

Stokes Parameter S1S_1S1: This parameter represents the difference in intensity between horizontally and vertically polarized waves. It indicates the linear polarization intensity along a specified axis.

The stokes parameter S2S_2S2:S2S_2S2 represents the difference in intensity between waves polarized at +45∘ +45^circ +45∘ and −45∘-45^circ – 45∘. It provides information about linear polarization along the diagonal axis.

The Stokes parameter S3S_3S3:S3S_3S3 represents the difference in intensity between right and left circular polarized waves. It indicates the circular polarization intensity.

These parameters are dimensionless and are usually normalized by dividing each by S0S_0S0, the total intensity parameter, to normalize for total power variations.

The parameters of a polarization ellipse describe the geometric properties of elliptically polarized light or electromagnetic waves. An elliptically polarized wave can be characterized by the following parameters:

are the normalized Stokes parameters

Elliptity ϵ epsilonϵ: Ellipticity quantifies how elliptical the polarization ellipse is. It is defined as the ratio of the minor axis (shorter axis) to the major axis (longer axis) of the polarization ellipse.

ORIENTATION ANGLE χ Chiχ: The orientation angle χ Chiχ specifies the orientation of the principal axis of the polarization ellipse with respect to a reference axis (often the horizontal axis). It varies from 0∘0 ^ circ0∘ to 180∘180 ^ circ180∘ and determines the direction of the polarization ellipse in the plane perpendicular to the direction of wave propagation. .

These parameters provide a concise description of the polarization state of electromagnetic waves beyond simple linear or circular polarization, capturing the nuances of elliptical polarization states that are common in various natural and artificial sources of electromagnetic radiation.

We trust this overview of What are the normalized Stokes parameters? has been clear.