A. R. Md Zain

High Quality-Factor 1-D-Suspended Photonic Crystal/Photonic Wire Silicon Waveguide Micro-Cavities

We have successfully fabricated and characterized suspended one-dimensional (1-D) photonic crystal/photonic wire (PhC/PhW) waveguide micro-cavities based on silicon-on-insulator (SOI). Our experiments have shown an enhancement of the resonance Q -factor from 18 700 to approximately 24 000, with normalized optical transmission of 70%, after removing the silica cladding underneath the silicon waveguide. We have also demonstrated that, for this condition, the resonance peak wavelength can be controlled by varying the length of the micro-cavity. These results were obtained by removing the silica cladding below the silicon waveguide to produce a ldquohangingrdquo wire waveguide. The three-dimensional (3-D) finite-difference time domain (FDTD) simulation approach used shows good agreement with measured results.

Control of coupling in 1D photonic crystal coupled-cavity nano-wire structures via hole diameter and position variation

We have successfully demonstrated close experimental control of the resonance splitting/free spectral range of a coupled micro-cavity one-dimensional photonic crystal/photonic wire device structure based on silicon-on-insulator. Clear splitting of the resonances, with FSR values ranging from 8 nm to 48 nm, was obtained through the use of different hole arrangements within the middle section of the device structures, between the coupled cavities. The results show good agreement with calculations obtained using a finite-difference time-domain simulation approach.

DUV phase mask for 100 nm period grating printing

Whereas microelectronic lithography is heading to the 32 nm node and discussing immersion and double-patterning strategies, there is much which can be done with the 45 nm node in microoptics for white light processing. For instance, one of the most demanding applications in terms of achievable period is the LCD lossless polarizer, which can transmit the TM polarization and reflect the TE polarization evenly all through the visible spectrum - provided that a 1D metal grid of 100 nm period can be fabricated. The manufacture of such polarizing panels cannot resort to the step & repeat cameras of microelectronics since the substrates are too large, too thin, too wavy and full of contaminants. There is therefore a need for specific fabrication techniques. It is one of these techniques that a subgroup of partners belonging to two of the Networks of Excellence of the European Community, NEMO and ePIXnet, have decided to explore together.

Performance evaluation of the UHF class 0 RFID tag for the proposed anti-collision algorithm

The Radio Frequency Identification (RFID) system is an automatic identification technology of choice over other existing technologies. Nowadays, the ability to identify many objects simultaneously is crucial for more advanced applications such as to identify objects in the warehouse and at the supermarket. These applications require an efficient identification technique which can identify many objects at one time without long delay. Meanwhile, one of the main issues during the identification process is the tags collision which occurs when all these tags are simultaneously responding to the reader commands. The RFID applications also require the tag to be simple, small, cheap and memoryless. Therefore the research is to evaluate the the performance of the proposed tag architecture for the Fast Detection Anti-collision Algorithm (FDACA) using the Total Tag Replies parameter. The Total Tag Replies parameter for the Binary Tree and the proposed FDACA tags are explained. The tag architecture for both techniques are described in Verilog Hardware Description Language (HDL) and simulated using Xilinix software. Then both tag architectures are synthesized using Application Specific Integrated Circuit (ASIC) technology (0.18 μm Library, Synopsys Compiler and tools). The tags performances are evaluated based on the obtained synthesis parameters.

Design of optical single mode splitter using ion exchange method for ammonia biosensor

One reasonable and cost-effective method to sense chemicals such as ammonia is to use optical waveguides. In this work, the simulation of an optical single-mode splitter waveguide was executed to detect ammonia on the sensing arm. OptiBPM and Ionex softwares were used for the waveguide and ion exchange simulations respectively. The deepest and widest optical channel was produced when a concentration of Ag+ of 0.2 moles/m3 was used at a temperature of 350°C for duration of 35 minutes. The optical splitter designed in OptiBPM showed a change in the optical power with the presence of ammonia on the gold-coated sensing arm of the splitter. Therefore, the thermal ion change method is an alternative cost-effective method for the fabrication of optical biosensors.

A Gallium Nitride Distributed Bragg Reflector cavity for integrated photonics applications

A deep etched 1D Distributed Bragg Reflector (DBR) cavity in GaN-AlN-Sapphire has been analytically modelled and simulated using 2D FDTD. A 3rd-order DBR has also been modelled including dye loaded polymer layer which can be used for emission enhancement characterization. A structure fabricated using a hybrid Electron Beam-Focused Ion Beam method was assessed using micro-photoluminescence.

All optical switching in silicon-on-insulator photonic wire nano-cavities

All-optical switching with a very low power is demonstrated on photonic crystal wire nano-cavities on silicon-on-insulator with large quality factors and high transmission in the telecom range.

All-optical logical operation in photonic wire nano-cavities

One of the major topics of interest in recent research on photonics is the study and development of photonic structures for fast signal processing signal for telecom applications. These kinds of structures are required to be compact and compatible with monolithic integration into one CMOS chip. The combination of one-dimensional photonic crystal structures with narrow waveguides in high refractive index contrast materials such as silicon-on insulator (SOI) can satisfy all the requirements.

All Optical Switching in Silicon-on-Insulator Photonic Wire Nano-Cavities

All optical switching in a silicon-on-insulator wire with a 1D photonic crystal nanocavity with ultra-high quality factor operating at telecom wavelengths is presented. Switching is performed with control pulse energy of only 20 fJ.