Circular Polarization of Electromagnetic Wave

Circular polarization is a type of polarization of electromagnetic waves where the electric field vector rotates around the direction of propagation of the wave. In order for an electromagnetic wave to exhibit circular polarization, the following condition must be met:

1. Two perpendicular components of equal amplitude

Circular polarization can be achieved when two perpendicular components of an electromagnetic wave have equal amplitude. These two components must be out of phase with each other by a 90-degree angle. One component should be horizontal and the other should be vertical.

2. Phase difference of 90 degrees

The two perpendicular components of the electromagnetic wave must have a phase difference of 90 degrees. This means that when one component is at its maximum, the other component should be at its minimum.

3. Constant magnitude of electric field

The magnitude of the electric field vector of the circularly polarized wave must remain constant. However, the direction of the electric field vector changes continuously as the wave propagates.

4. Non-zero net angular momentum

The circularly polarized wave must have a non-zero net angular momentum. This is because the electric field vector rotates around the direction of propagation of the wave, which creates a helical path for the wave.

Conclusion

In conclusion, circular polarization of an electromagnetic wave can be achieved when two perpendicular components of equal amplitude have a phase difference of 90 degrees, and the magnitude of the electric field vector remains constant while the direction changes continuously. Additionally, the circularly polarized wave must have a non-zero net angular momentum.