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A comment on 100G-LR4 optic cable teardown. Parent comment

Re:100G-LR4 optic cable teardown by extropy on Monday December 12, 2022 @03:05AM (#33952152)
That sounds very wrong. Not a physicist, but light does not interact with magnets, or you need to get into the superconducting strength levels before it does.

https://en.m.wikipedia.org/wiki/Optical_rotation

It seems the optical rotation happens due to molecular structure of specific materials.

Edit, found this: https://en.wikipedia.org/wiki/Faraday_effect

So a specific material plus magnetic field is needed. But still not sure how strong of a field is sufficient.

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Re:100G-LR4 optic cable teardown by tomn on Monday December 12, 2022 @06:11AM (#33953401)
For more details on this specific application these pages might be more relevant:

https://en.wikipedia.org/wiki/Optical_isolator

https://en.wikipedia.org/wiki/Faraday_rotator

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Re:100G-LR4 optic cable teardown by ycui1986 on Monday December 12, 2022 @11:48AM (#33956885)
Magnet there is probably used as an isolator. The laser can only go out,but not come back.( yes, there will be laser coming back from reflection, which also interrupt the operation of the source laser.
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