I Why is the electric field in y direction in a TE guided wave?

AI Thread Summary
In a transverse electric (TE) guided wave, the electric field is oriented in the y-direction because the mode requires that the electric field has no component in the direction of propagation (z-direction). The condition E_z = 0 is fundamental to TE modes, and E_x = 0 is necessary to maintain this polarization along the y-axis. The magnetic field component B_y is also zero in this configuration, consistent with the characteristics of TE modes. The discussion emphasizes that the orientation of the coordinate system is arbitrary, but the relationships between the fields remain consistent. Understanding these properties is crucial for analyzing wave propagation in rectangular waveguides.
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Direction of the electric field in a transverse electric guided wave.
Hi,
I have a fairly simple question, but the answer is probably not as simple.
I'm not sure to understand why in a guided wave (TE), the electric field is in the y direction.
I know ##E_z = 0##, but why ##E_x = 0, B_y = 0##?
 
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You will have to give details of the situation you are considering. The orientation of the cartesian coordinates is arbitrary.
 
I have wave guide of rectangular shape with height a and width b.
 
EpselonZero said:
I have wave guide of rectangular shape with height a and width b.
Along which axes?
 
Sorry,
##\hat{x}## is horizontal, ##\hat{y}## is vertical and the direction of propagation is ##\hat{z}##
 
EpselonZero said:
Sorry,
##\hat{x}## is horizontal, ##\hat{y}## is vertical and the direction of propagation is ##\hat{z}##
Then if ##E_x=0## is because the E field is polarized along y (i.e., it doesn't need to be 0). ##B_y = 0## since it is a TE mode.
 
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