Experimental confirmation of the concept of the photon spatial switch based on off-axis zone plate in the millimeter range

The results of an experimental verification of the concept of the previously proposed all-optical wavelength-selective multichannel switch based on an off-axis Fresnel zone plate in the millimeter wavelength range without the use of micromechanical devices or non-linear materials are presented. A laboratory prototype of such a device is considered and its main parameters are discussed. It is shown that the optical isolation of switched channels for a switch based on an off-axis zone plate can reach 15 dB at a frequency difference of 25 GHz in the frequency range of 93–136 GHz.