In this article, an optical full adder is investigated in terms of light flow inside the two‐dimensional (2‐D) crystal lattice waveguide structures. The phenomenon such as resonance, splitter, and combiner based on the principle of constructive and destructive interference is used in the modeling of all optical full adders. Also, defects are introduced in the junction of the waveguide structures to pass/stop light wave inside the waveguide structure. The designed full adder structure in 2‐D photonic crystals (PhCs) occupies an area of 382.91 μm2 and maximum light confinement at the Sum and Cout output ports are 0.52 and 0.6 arbitrary unit (a.u.), respectively. The response time of the full adder structure is about 0.25 ps and the maximum contrast ratio achieved at the Sum is 7.16 dB and Cout is 5.74 dB. RSoft FullWAVE simulation tool is used to perform a full‐vector simulation of photonic structures.
The presented research deals with designing of a new ultra compact all-optical RS flip-flop on a two-dimensional (2-D) hexagonal photonic crystal platform. The flip-flop is designed by using two NOR gates, photonic crystal waveguides, four silicon ring resonators, four input ports and two output ports. The designed flip-flop structure has hexagonal silicon rods in the air host with a lattice constant a of 630 nm. Si rods have a radius of 0.2a and operating waveleangth of 1550 nm. The novel design provides proper distinction between logic 1 and logic 0 at the output by giving 8.7 dB and 4 dB contrast ratio at Q and Qbar output, respectively. Furthermore, uncomplicated structure resulting in small dimension of 28 μm * 28 μm makes it appropriate for optical integrated circuit in optical networks. FDTD method is used to model the proposed structure and simulated using RSoft FullWAVE simulator tool.
In this paper all optical ultra compact 4:2 encoder is proposed and designed using two dimensional photonic crystals. The proposed structure has silicon rods of refractive index of 3.4 embedded in air host by creating line defects in hexagonal lattice platform. PWE method is used to determine the photonic band gaps and structure is analyzed using FDTD method. Further, the proposed 4:2 encoder is operated at 1550 nm and it provides a high contrast ratio of 9.25dB and foot print of the structure is 119.34 μm 2 . Hence it is highly advisable for photonic integrated circuits and optical signal processing.
The proposed encoder in two dimensional photonic crystals is analyzed interms of flow of light inside waveguides. Waveguides have been created by removing silicon rods in the structure and defects with smaller radii have been created to achieve the proper couplers operations. The photonic band gap of the proposed encoder is determined and their performance is evaluated using finite difference time domain method. The proposed design has an optical output power threshold range between 76-94% for ON state and threshold level of OFF state is below 20%. The proposed encoder is operated in the wavelength of 1550 nm. Hence, it is applicable for high speed optical integrated circuit. The response time and contrast ratio calculated from the proposed encoder are 0.24 ps and 8.59 dB which are comparatively better than the literature reported with compare to footprint area of the proposed encoder.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.