Embedding defect sites into hexagonal nondiffracting wave fields

Abstract

We present a highly purposive technique to optically induce periodic photonic lattices enriched with a negative defect site by using a properly designed nondiffracting (ND) beam. As the interference of two or more ND beams with adequate mutual spatial frequency relations in turn reproduces an ND beam, we adeptly superpose a hexagonal and a Bessel beam to create the ND defect beam of demand. The presented wavelength-independent technique is of utmost universality in terms of structural scalability and does not make any specific requirements to the photosensitive medium. In addition, the technique is easily transferable to all pattern-forming holographic methods in general and its application is highly appropriate, e.g., in the fields of particle as well as atom trapping.

Spatial light modulator based holographic fabrication of 3D spatially varying photonic crystal templates

“…27 Setups incorporating spatial light modulators present new opportunities to fabricate many of the same structures as traditional holographic lithography setups by generating the appropriate intensity profiles using computer generated holograms. [28][29][30][31][32][33][34][35][36][37][38]41 Computer generated holograms on phase-only SLMs have proven effective in generating multi-beam interferences, which are capable of fabricating periodic, [29][30][31][32][33] quasi-periodic structures, 28 and chiral photonic crystals. 31 By incorporating higher Fourier order into the phase pattern in conjunction with an amplitude SLM, multiperiodic lattices can be formed.…”

“…31 By incorporating higher Fourier order into the phase pattern in conjunction with an amplitude SLM, multiperiodic lattices can be formed. 32 Defect sites can be incorporated into a photonic lattice using an SLM with superposition of a Bessel beam into the interference pattern, 34,35 or by specifying the gray levels of a simple geometric phase pattern. 36 Even waveguides embedded in 2D and 3D photonic crystals are possible using an SLM.…”

Holographic fabrication of photonic crystal templates using spatial-light-modulator-based phase mask method

“…30 By engineering the phase pattern to superimpose a Bessel beam into an interference pattern, defect sites can be created in a photonic lattice in a photosensitive medium. 31,32 In this paper, we use a geometric, grayscale phase pattern displayed on the SLM to demonstrate the digital assignment of phase to diffracted beams. The relationship between the gray levels in the phase pattern displayed on the SLM and the phases of the individual beams is calculated.…”

Optical generation of a spatially variant two-dimensional lattice structure by using a phase only spatial light modulator

“…A single step, low cost, large area fabrication of periodic (or quasi periodic) photonic crystal structures is possible by the method of interference lithography 5,6 and few recent advances with phase only spatial light modulator (SLM) assisted interference lithography has enabled the fabrication of some unconventional photonic crystal structures. These structures include embedding of defect sites [7][8][9] , creation of line defects 10 , dual lattice structures 11 and gradient structures 12,13 . This approach is better than other fabrication approaches like e-beam lithography 14 or direct laser writing 15 because they being serial in nature are prone to errors and are time consuming.…”