title: Diffraction control of subwavelength structured light beams in Kapitza media.
abstract: Kapitza tandem structures, consisting of thin alternating layers with opposite signs of the dielectric permittivity, have been recently predicted to afford diffraction arrest of focused microwave radiation [Phys. Rev. Lett. 110, 143901 (2013)]. Here we study the applicability of the Kapitza effect to control the propagation of structured subwavelength light beams. We show that a sufficiently deep modulation of the dielectric permittivity allows a nearly complete diffraction cancellation of multiple-peak subwavelength beams, and we study how the degree of diffraction cancellation decreases as the spatial spectrum of the input beam broadens. We also find that subwavelength light beams can be steered by varying the depth of the permittivity modulation. In particular, a sufficiently large permittivity modulation is shown to cause otherwise titled inputs to propagate always along the direction of modulation.
authors.forename: Changming
authors.initials: C
authors.lastname: Huang
authors.forename: Fangwei
authors.initials: F
authors.lastname: Ye
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Chen