Determining the Handedness of Circular Polarized Waves

[mrshappy0]

Homework Statement

A polarized wave in the y axis, propagates in the z axis and is incident to a quarter-wave plate. Viewing the down from -z to z, the fast axis is 45deg below the x-axis.

Determine the polarization of the beam immediately following the quart-wave plate.

Homework Equations

Conceptual Question, I am not using equations..

The Attempt at a Solution

The wave must be circular but I cannot visualize how to determine whether it is left handed or right handed. I realize that if you curl your fingers in the direction that it rotates, the hand with the thumb pointing in the direction of propagation is the handedness but I can't visualize how the wave curls coming out.

 

[mrshappy0]

Haven't seen any replies yet so I am curious if there are any issues with this post.

 

[mrshappy0]

Well, I thought about it as I drifted off to sleep last night and I was thinking that crossing from from the slow axis (which must be orthogonal in this case) to the fast axis with the left hand allows for the thumb to be pointed in the direction of propagation. By doing this, I get a left handed curl. Is this correct? So in this case, it doesn't matter where the wave is polarized, as long as it has a non-zero component for the fast axis and a non-zero component for the slow axis, right??

Here is the image I drew for what I am doing.

 

[mrshappy0]

I believe if you were to apply the image above to the problem I posted, the fast and slow axis must be switched giving a right handed circle, I think.

 

[Nickie]

I would approach this problem by first understanding the properties and behaviors of circular polarized waves. Circular polarized waves are characterized by their direction of rotation, which can be either left-handed or right-handed. This direction of rotation is determined by the orientation of the electric and magnetic fields of the wave.

In this scenario, the wave is incident to a quarter-wave plate, which is a device that can change the polarization of a wave. By viewing the wave from -z to z, we can determine that the fast axis of the quarter-wave plate is 45 degrees below the x-axis. This means that the wave's electric field is rotated by 45 degrees as it passes through the quarter-wave plate.

To determine the handedness of the circular polarized wave after passing through the quarter-wave plate, we can use the right-hand rule. If we curl our fingers in the direction of rotation of the wave, our thumb will point in the direction of propagation. By doing this, we can determine that the wave is left-handed, as the direction of rotation is counterclockwise when viewed from the -z direction.

In conclusion, the wave immediately following the quarter-wave plate is left-handed circular polarized, with its electric and magnetic fields rotating counterclockwise as it propagates in the z direction.