Fairuz Diyana Ismail

Blood cleaner on-chip design for artificial human kidney manipulation

A novel design of a blood cleaner on-chip using an optical waveguide known as a PANDA ring resonator is proposed. By controlling some suitable parameters, the optical vortices (gradient optical fields/wells) can be generated and used to form the trapping tools in the same way as optical tweezers. In operation, the trapping force is formed by the combination between the gradient field and scattering photons by using the intense optical vortices generated within the PANDA ring resonator. This can be used for blood waste trapping and moves dynamically within the blood cleaner on-chip system (artificial kidney), and is performed within the wavelength routers. Finally, the blood quality test is exploited by the external probe before sending to the destination. The advantage of the proposed kidney on-chip system is that the unwanted substances can be trapped and filtered from the artificial kidney, which can be available for blood cleaning applications.

ALL-OPTICAL SWITCHES BASED ON GaAs/AlGaAs QUANTUM DOTS VERTICAL CAVITY

In this paper, an all-optical switch based on self-assembled GaAs/AlAs quantum dots (QDs) within a vertical cavity is designed and proposed. Two essential aspects of this novel device have been investigated, which include the QD/cavity nonlinearity with appropriately designed mirrors and the intersubband carrier dynamics inside QDs. The vertical-reflection-type switches have been investigated with an asymmetric cavity that consists of 12 periods of GaAs/Al0.8Ga0.2As and 25 periods for the front and back mirrors, respectively. The thicknesses of the GaAs and AlGaAs layers are chosen to be 89 and 102 nm, respectively. To give a dot-in-a-well (DWELL) structure, the 65 nm dimension of Si was recommended to deposit within a 20 nm AlAs QW. Results obtained have shown that all-optical switching via the QD excited states has been achieved with a time constant down to 275-fs and over 29.5 nm tunable wavelengths. These results demonstrated that QDs within a vertical cavity have great potential to realize low-power, consumption polarization-insensitive and micrometer-sized switching devices for future optical communication and signal processing systems.

Fast Faraday cup for fast ion beam TOF measurements in deuterium filled plasma focus device and correlation with Lee model

In this work, the design and construction of a 50 Ω fast Faraday cup and its results in correlation with the Lee Model Code for fast ion beam and ion time of flight measurements for a Deuterium filled plasma focus device are presented. Fast ion beam properties such as ion flux, fluence, speed, and energy at 2–8 Torr Deuterium are studied. The minimum 34 ns full width at half maximum ion signal at 12 kV, 3 Torr Deuterium in INTI PF was captured by a Faraday cup. The maximum ion energy of 67 ± 5 keV at 4 Torr Deuterium was detected by the Faraday cup. Ion time of flight measurements by the Faraday cup show consistent correlation with Lee Code results for Deuterium especially at near to optimum pressures.

Spectroscopic diagnostics of laser induced plasma and self-absorption effects in Al lines

Self-absorption (SA) can drastically affect the emission signal which makes quantitative and, in extreme cases, qualitative investigations very challenging in laser induced plasma spectroscopy. In this study, plasma parameters are spectroscopically studied and SA in aluminum emission lines is investigated at various laser energies and gate delays. Q-switched Nd:YAG laser installed on LIBS2500plus system (1064 nm, 6 ns, 10 Hz) was used for ablation. The sample was ablated in air with different laser energies between 5 and 650 mJ, and spectra were recorded at various gate delays between 0 and 23.75 μs. Intensities of spectral lines Al I 308.2 and 309.3 nm were monitored for the range of laser energies and gate delays. The intensity of spectral lines was increased in response to the increasing laser energy. Rapid increase in intensities was observed for the first microsecond after plasma ignition. The maximum intensity of Al is observed at a gate delay of 1.25 μs. Plasma conditions are investigated on the basis of electron density and temperature in response to the change in laser energy and gate-delay. The electron temperature increased from 15 413 K to 20 200 K and the electron density from 5.0 × 1016 cm−3 to 3.5 × 1018 cm−3 with increase in laser energy from 5 to 650 mJ. The electron temperature is exponentially decreased from 26 733 K to 16 649 K and the electron density is reduced from 2.0 × 1017 cm−3 to 1.0 × 1016 cm−3 for increase in the gate delay from 0 to 23.75 μs. The self-absorption effect in resonant spectral lines of Al is estimated on the basis of SA coefficient calculated using FWHM of spectral lines. The highest values of SA coefficient are found for the lowest laser energies and longest gate delays. It states that the SA is significant when the plasma temperature is low and also, when plasma is least dense. It is fairly obvious to conclude that SA effects are least prevalent when the plasma plume is induced by high laser energies and measurements are made at short gate delays.Self-absorption (SA) can drastically affect the emission signal which makes quantitative and, in extreme cases, qualitative investigations very challenging in laser induced plasma spectroscopy. In this study, plasma parameters are spectroscopically studied and SA in aluminum emission lines is investigated at various laser energies and gate delays. Q-switched Nd:YAG laser installed on LIBS2500plus system (1064 nm, 6 ns, 10 Hz) was used for ablation. The sample was ablated in air with different laser energies between 5 and 650 mJ, and spectra were recorded at various gate delays between 0 and 23.75 μs. Intensities of spectral lines Al I 308.2 and 309.3 nm were monitored for the range of laser energies and gate delays. The intensity of spectral lines was increased in response to the increasing laser energy. Rapid increase in intensities was observed for the first microsecond after plasma ignition. The maximum intensity of Al is observed at a gate delay of 1.25 μs. Plasma conditions are investigated on the ba...

Computationally numerical experiment of carbon species densities for thermal plasma dynamic

The present work develops a computationally effective one-dimensional sub grid set in numerical integration for density formulation from thermal plasma. The model incorporates two-body and more collision effects throughout Carbon plasma using continuity equation. The carbon gas inter electrode gap is accelerated by the electric field to produce plasma. In this model the reaction processes of carbon species is identified. The extrapolation of species dominant in arc discharge process is critical issue in significant for predicting carbon nanostructure production. In this paper, we describe chemical kinetic models and their possibilities of carbon ion and neutral species production based on collisions and time dependence. The results show the reaction rate of Carbon ions calculated at 7.85 × 1028 m-3 s-1 while the temperature increment decreases, the reaction rate is up to 6.25 × 1027 m-3 s-1. The electron density reduces until 108 m-3 from initial condition at 1 atm. However, the electron density increases 1013 m-3 from 0.05 eV-0.3 eV. The ionization of Carbon reaction has been affected by pressure and temperature which gains a quantitative understanding of the density at equilibrium state.

Numerical simulation of spherical plasma focus device using Lee model

Summary form only given. The plasma focus device is a potential source for multi-radiation emission. Lee model has been developed with a complete description of the plasma focus dynamics to simulate the plasma motion in both the axial and radial phase. The code couples the electrical circuit with plasma focus (PF) dynamics, thermodynamics and radiation. Spherical plasma focus device is a special case between Mather and Filippov configurations. Spherical electrodes made the chamber design more compact when compare to Mather-type and Filippov-type. In this study, numerical simulation for spherical plasma focus device using Lee model has been performed to test the universality of Lee model. Experimental results from a spherical plasma focus device is compared with numerical simulations results in terms of neutron yield and X-ray radiation for different gases and at different pressure.