Polarization and intensity of a Gaussian beam

• Sciencestd
In summary, the equation assumes that the Gaussian beam has polarization in the x-direction, meaning that the electric field oscillates in that direction and determines the intensity. The direction of the polarization is arbitrary and can be perpendicular to the z-axis. Intensity is a scalar and cannot be described as "linear" or "circular." The polarization vector of the electric field decreases in size as you move away from the center, but still points in the same direction. The shape of the intensity is determined by the direction of the polarization.
Sciencestd

The equation above (from Wikipedia), assumed that the Gaussain beam has polarization in x-direction, as I know that the polarization means that the oscillation direction of the electric field and so the intenisty... so how we get circular intensity in every direction which means in x and y, above mentioned it with "r"... I can't connect between the two things..
Thank you.

Last edited:
The versor along the x direction is arbitrary. Any direction, perpendicular to z, is valid.

Sciencestd
In addition, intensity is a scalar. We don't have "linear" or "circular" intensity.

Sciencestd
Gordianus said:
In addition, intensity is a scalar. We don't have "linear" or "circular" intensity.
Thank you so much for the answers. So what decide the intensity shape?
And the second question can I say that the polarization vector of the electric field is shorter and shorter in the sides?

When you move away from the center the electric field gets smaller but it points in the same direction.

Sciencestd

1. What is the difference between polarization and intensity of a Gaussian beam?

Polarization refers to the direction of the electric field oscillations in a light wave, while intensity refers to the amount of energy carried by the light. A Gaussian beam can have different polarization states, such as linear, circular, or elliptical, while its intensity remains constant along the beam profile.

2. How is the polarization of a Gaussian beam determined?

The polarization of a Gaussian beam is determined by the orientation of the electric field vector with respect to the direction of propagation. This can be controlled by using polarizers or waveplates to manipulate the polarization state of the beam.

3. What factors affect the intensity of a Gaussian beam?

The intensity of a Gaussian beam is primarily affected by the beam's power and its beam waist, which is the point of maximum intensity along the beam profile. Other factors that can affect intensity include the beam's divergence, wavelength, and any obstructions or imperfections in the optical setup.

4. How does the polarization of a Gaussian beam change as it propagates through a medium?

As a Gaussian beam propagates through a medium, its polarization can be affected by various factors such as birefringence, optical activity, and scattering. These effects can cause the polarization state of the beam to change, leading to changes in its intensity and other properties.

5. Can the polarization and intensity of a Gaussian beam be measured?

Yes, the polarization and intensity of a Gaussian beam can be measured using various techniques such as polarimetry, interferometry, and photodetection. These methods allow for precise measurements of the beam's properties, which are important for many applications in optics and photonics.

• Optics
Replies
5
Views
3K
• Optics
Replies
3
Views
828
• Optics
Replies
2
Views
834
• Optics
Replies
3
Views
1K
• Quantum Physics
Replies
8
Views
1K
• Optics
Replies
4
Views
3K
• Atomic and Condensed Matter
Replies
0
Views
553
• Optics
Replies
5
Views
2K
• Classical Physics
Replies
5
Views
908
• Optics
Replies
6
Views
13K