# Non reciprocal light propagation

In search for some explanation in why magneto-optical materials (like the one used in the Faraday rotator and, consequently, in the "optical diode") act in such a "strange" way, I saw that this kind of materials break the time-reversal symmetry and a different kind of reciprocity is applicable, the Rayleigh-Carson one.

What I cant figure out is how the interaction of the the light with the material can rotate de polarization vector depending on the direction? How can I visualizate it in a microscopic level (using Quantum Mechanics)?

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