Non-reciprocal one-way transparent sheets

Electrically thin layers formed by infinite periodical arrays of uniaxial lossless particles are under study. The layers are illuminated by normally incident plane waves. Here we derive the required polarizabilities of the particles such that the layers composed of them are totally transparent for illumination from one side but show different electromagnetic properties from the other side. We show that non-reciprocal electromagnetic coupling is necessary to realize one-way transparent sheets.