Spatial Beam Compression and Effective Beam Injection Using Triangular Gradient Index Profile Photonic Crystals

Abstract

Abstract-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.

Exponentially index modulated nanophotonic resonator for high-performance sensing applications

“…Later, it was looked into for several uses, including couplers 19 , optical lenses 20 , mode converters 21 , 22 , and optical multiplexers 23 , 24 . Major applications of optical length modulated grade PhC structure include super bending, super collimation, high-efficiency couplings, super lensing, beam aperture modifier, and deflector 25 , 26 . Refractive index modulation is another widely explored method to study the band-gap features of the PhC structures.…”

Asymmetric Light Propagation Based on Graded Photonic Crystals

“…17) The horizontal period of the PC was changed linearly, and the asymmetric light propagation was achieved because of the band gap structure of chirped PC waveguides. GPCs are obtained through appropriate gradual modifica-tions of PC parameters, such as the filling factor, [23][24][25][26][27] the optical index, 24,27) the lattice period, 17,28) or the sharp points of dielectric rods. 29) In 2006, Roux and De Leon 26) successfully implemented a two-dimensional (2D) gradient index (GRIN) lens in a 2D photonic crystal, and this gradient index is achieved by varying the radii of the air holes in the hexagonal photonic lattice.…”

Tiles of non-moiré photonic structures for tailoring the light path with multi-channel waveguiding and beam steering

“…Based on PBG and anomalous dispersion in PhCs, at least four classes of PhCs namely (I) gradient and spatially variant PhCs, 10,11) (II) heterostructure PhCs, 12) (III) plasmonic PhCs, 13) and (IV) quasi-periodic, topological, and Archimedean lattices [14][15][16] can be indicated for novel waveguiding techniques. In I type, adiabatic variation in the size/ orientation, and optical constants of the photonic atom allows one to engineer the light path with the user-controlled specification.…”