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Electromagnetic properties of resonant metasurfaces are studied in transition from a periodic to an amorphous arrangement of their constituents. Emphasis is put to investigate the response at oblique incidence and for TM polarized light. Our metasurfaces possess both electric and magnetic resonances which makes them to be canonical samples that reflect properties of many metasurfaces. The suggested analytical model explains many if not to say all far-field optical properties that can be observed in resonant metasurfaces. For example, the resonance broadening and damping for the electric mode which contrasts with the persistence of these properties for the magnetic mode in transition from crystalline to the amorphous state can be fully explained. All theoretical predictions are verified with complementary numerical calculations and experimental measurements. [ABSTRACT FROM PUBLISHER]

In this presentation we discuss the results of our recent theoretical studies of electromagnetic reflection, transmission, and scattering properties of periodic and random arrays of particles which exhibit both electric-mode and magnetic-mode resonances. We compare the properties of regular and random grids and explain recently observed dramatic differences in resonance broadening in the electric and magnetic modes of random arrays. We show that randomness in the particle positioning influences equally on the scattering loss from both electric and magnetic dipoles, however, the observed resonance broadening can be very different depending on the absorption level in different modes as well as on the average electrical distance between the particles. The theory is illustrated by an example of a planar metasurface composed of cut-wire pairs. We show that in this particular case at the magnetic resonance the array response is almost not affected by positioning randomness due to lower frequency and higher absorption losses in that mode. The developed model allows predictions of behavior of random grids based on the knowledge of polarizabilities of single paticles. The study is relevant to understanding of electromagnetic response of complex composite layers, especially manufactured using self-assembly techniques. [ABSTRACT FROM PUBLISHER]