Experimental Demonstration of Self-Collimation inside a Three-Dimensional Photonic Crystal

Abstract

We present our experimental demonstration of self-collimation inside a three-dimensional (3D) simple cubic photonic crystal at microwave frequencies. The photonic crystal was designed with unique dispersion property and fabricated by a high precision computer-controlled machine. The self-collimation modes were excited by a grounded waveguide feeding and detected by a scanning monopole. Self-collimation of electromagnetic waves in the 3D photonic crystal was demonstrated by measuring the 3D field distribution, which was shown as a narrow collimated beam inside the 3D photonic crystal but a diverged beam in the absence of the photonic crystal.

3d Printed Lattices With Spatially Variant Self-Collimation

“…bend without diffracting or scattering. Self-collimation [38][39][40][41][42][43][44] is a phenomenon where a beam propagates without diffraction and is forced to flow in a specific direction relative to the principal axes of the unit cells. Using this effect, a beam can be made to flow along an arbitrarily curved path by spatially varying the orientation of the unit cells.…”

Ultrafast evolution of photonic eigenstates in k-space

“…This relation is usually not straightforward: owing to the imposed periodicity, bands are folded into every Brillouin zone, inducing splitting of bands and the appearance of bandgaps. As a result, exciting phenomena such as negative refraction 6,7 , autocollimation of waves 8,9 and low group velocities 10-12 arise. k-space investigations of electronic eigenstates have already yielded new insights into the behaviour of electrons at surfaces and in novel materials [13][14][15][16] .…”

Optical wave parameters for spatially dispersive and anisotropic nanomaterials

“…It can be a photonic crystal [26,27] or a metamaterial [10,11,28,29]. Ideally, the refractive index of such a medium should be given by…”