Magnetic field detectable around axis of laser beam?

AI Thread Summary
The discussion centers on the detection of magnetic fields around the axis of a laser beam in a vacuum. Participants explore whether magnetic field flux extends beyond the beam axis and if it can be detected without interrupting the beam. A reference to Bessel beams is made, indicating that the magnetic field oscillates and diminishes as it moves away from the axis. The conversation highlights the complexity of the topic and the need for further exploration. Overall, the potential for detecting magnetic fields around laser beams remains an intriguing area of inquiry.
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I've looked for this subject but perhaps I'm asking the question the wrong way. Please advise.
Is there an extension of magnetic field (flux) beyond the beam axis of a laser? In other words, can one detect (or has anypone attempted to detect) the magnetic field around the a light beam in a vacuum without actually entering or interupting the beam?

Thanks
G
 
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I'm sure of the correct answer. But I once looked up what the radially symmetric solution to a wave propagating in one direction is.

The only solutions is Bessel beams
http://arxiv.org/abs/physics/0006046 (page 6)

The magnetic field oscillates and falls off as 1/\sqrt{\varrho}

Maybe that's the answer.
 
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