Spatial beam compression and effective beam injection using triangular gradient index profile photonic crystals

Spatial beam compression of an electromagnetic wave is one of the fundamental techniques employed in microwaves and optics. As there are many ways to achieve this task using the combination of prisms and lenses, recent research suggests the parabolic gradient index photonic crystals (GRIN PC) for the design of spatial beam compressor owing to its functionalities. However, the fabrication of a graded media with the parabolic profile is a difficult challenge in practical realization. As an alternative, present work attempts this problem with respect to the triangular gradient index profile. The performance and aspects of the beam compression are investigated experimentally using the pillar type GRIN PC at the microwave length-scales. The utility of the device for an effective beam injection to the photonic-waveguide component is further demonstrated experimentally.