Nor Azura Malini Ahmad Hambali
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Preferred name
Nor Azura Malini Ahmad Hambali
Official Name
Nor Azura Malini, Ahmad Hambali
Alternative Name
Hambali, N. A. M. Ahmad
Hambali, N. A. M. A.
Hambali, Nor Azura Malini Ahmad
Idris, N. A.
Hambali, N. Azura M. Ahmad
Main Affiliation
Scopus Author ID
27567626900
Researcher ID
JFK-8606-2023

Research Output

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  • Publication
    Thermal analysis of LED packaging with single-walled carbon nanotube heat sink
    ( 2023-12)
    C. K. Keong
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Norshamsuri Ali @ Hasim
    ;
    H. Mohamad
    The thermal issue is still the bottleneck of a light emitting diode (LED) system to sustain its operational performance. In this paper, we design, simulated, and analysed an LED packaging with single walled carbon nanotubes as a heat sink. The 5W LED packaging is simulated with different types of LED chips materials which comprise gallium nitride, indium nitride, zinc oxide, zinc selenide and titanium dioxide. Using LED chips materials as the heat source, the heat flow is conducted through the bottom layer to the heat sink and dissipates by convection or radiation heat transfer to the surrounding. The addition of thin film on top of the phosphorus layer functions to enhance the recombination rate and guided the flow of heat to the bottom. The 5W titanium dioxide light emitted diode packaging (LED packaging C) has been successfully demonstrated to have overall temperature reduced to around ~10°C by using single walled carbon nanotube heat sink as compared to copper heat sink and aluminium heat sink. Meanwhile, carbon material as thermal interface material and substrate also plays a major role as a thermal cooling solution in LED packaging. For 5W titanium dioxide light emitted diode packaging, under self-heating conditions, the maximum average temperature generated is 81.05 °C. Despite that, under convection conditions, the maximum average temperature generated is 41.53°C.
  • Publication
    UWB triplet and quadruplet pulses generation employs nonlinear effect in semiconductor optical amplifier nonlinear loop mirror
    ( 2020-01-08)
    Zahari, Suhaila Mohd
    ;
    Mohamad Halim Abd. Wahid
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Nurjuliana Juhari
    ;
    Ghazali N.F.
    ;
    Shahimin M.M.
    Ultrawideband (UWB) triplet and quadruplet pulses generation exploits nonlinear effect in semiconductor optical amplifier (SOA) in nonlinear loop mirror (NOLM) is investigated in this work. Two signals are transmitted through the SOA-NOLM simultaneously to create cross-phase modulation (XPM) effect. Firstly, the XPM causes the production of doublet which later combines for creation of triplet and quadruplet. This technique engages a proper tuning of optical delay and a selection of suitable power in all loops. Besides, injection current of the SOAs also governs the formation of these pulses. Although, frequency of the signals can be varied accordingly, the pulses are limited to certain adjustment that shifted its position in time domain. Furthermore, the set up can also be assessed for monocycle and doublet pulses by extracting the output at several positions. It can be concluded that the design may work as multiple pulses generation. All pulses are examined and compared with their electrical spectrum counterpart for validity of this approach.
  • Publication
    Remazol orange dye sensitized solar cell
    ( 2017-01-03)
    Siti Salwa Mat Isa
    ;
    Muhammad Mahyiddin Ramli
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Muda M.R.
    ;
    Shahrir Rizal Kasjoo
    ;
    Muammar Mohamad Isa
    ;
    Nurul Izza Mohd Nor
    ;
    Norhawati Ahmad
    ;
    Nazuhusna Khalid
    ;
    Nur M. Selamat
    ;
    Nur Asyikin Mohd Anhar
    Water based Remazol Orange was utilized as the dye sensitizer for dye sensitized solar cell. The annealing temperature of TiO2 working electrode was set at 450 °C. The performance of the device was investigated between dye concentrations of 0.25 mM and 2.5 mM at three different immersion times (3, 12 and 24 hours). The adsorption peak of the dye sensitizer was evaluated using UV-Vis-Nir and the device performance was tested using solar cell simulator. The results show that the performance was increased at higher dye concentration and longer immersion time. The best device performance was obtained at 0.2% for dye concentration of 2.5 mM immersed at 24 hours.
  • Publication
    Loop Mirror Multi-wavelength Brillouin Fiber Laser Utilizing Semiconductor Optical Amplifier and Fiber Bragg Grating
    ( 2017-02-01)
    Najwa Idris
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Ariffin N.
    ;
    Shahimin M.
    ;
    Mohd. Azarulsani Md. Azidin
    In this paper, the development of loop mirror multi-wavelength Brillouin fiber laser utilizing semiconductor optical amplifier and fiber Bragg grating is successfully demonstrated. A multi-wavelength BFL structure employs a single mode fiber that acts as the gain medium, while the fiber Bragg grating act to reflect the signals and semiconductor optical amplifier is used to amplify the signal are employed to produce multiple channels. The implementation of difference parameter for semiconductor optical amplifier driven current, Brillouin pump power, Brillouin pump wavelength and length of single mode fiber, plays an important role in producing the multiple channels. The highest number of channels which is 15 achieved once 9 km of SMF length, semiconductor optical amplifier current at 800mA and low Brillouin pump power at-12 dBm are utilized in the laser structure. Furthermore, the implementation of semiconductor optical amplifier and reflectivity of fiber Bragg grating in Brillouin fiber laser structure gives a better performance in producing the multiple channels.
  • Publication
    Generation Orbital Angular Momentum Modes Using Metasurfaces
    ( 2023-10-06)
    NHuda S.
    ;
    Norshamsuri Ali @ Hasim
    ;
    Amphawan A.
    ;
    Nor Roshidah Yusof
    ;
    Rosdisham Endut
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohd Najib Mohd Yasin
    ;
    Syed Alwee Aljunid Syed Junid
    The purpose of this study is to investigate how numerous orbital angular momentum (OAM) modes may be produced by mixing acoustic plane beams with different metasurfaces. This study proposes a novel metasurface that may be simulated in order to generate OAM beams. Multi-beam and multi-mode terahertz wave incidence are produced utilizing vortex modes in the beams. The study of suitable OAM superpositions of waveguide eigenmodes is done using COMSOL Multiphysic, followed by a description of the software's usage and examples of challenges involved. With the existence of these studies, we can also prove that the mode can be produced completely with the results that have been studied. Based on the results obtained, an objective was achieved, which is to design the feature of the vortex beam modes. These results include the construction of a multi-functional vortex beam based on a theoretical model of phase gradient distribution. Also, by using metasurface mimics to specify a periodic structure specified by the user from the built-in unit cell, and the beam was attenuated and split into two paths inside the thin layer. Finally, the simulation process between 2D and 3D is very significant because the mesh and geometry in a design are very different, but generating a beam using COMSOL already has a specific module, namely the wave optic module, which can be used to predict the beam modes.
  • Publication
    Characteristics of multiwavelength fiber laser employing semiconductor optical amplifier in nonlinear optical loop mirror with different length polarization maintaining fiber
    ( 2020-01-08)
    Husshini N.F.H.
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Shahimin M.
    ;
    Mohd Najib Mohd Yasin
    ;
    Norshamsuri Ali @ Hasim
    ;
    Al-Asadi H.A.A.
    In this paper, we propose and demonstrate generated characteristics of a multiwavelength fiber laser based on semiconductor optical amplifier in a nonlinear optical loop mirror with different length of polarization maintaining fiber. The configuration comprises 3-dB optical coupler, semiconductor optical amplifier and, 2 meters and 10 meters of polarization maintaining fiber. Characteristics of multiwavelength fiber laser are studied through the use of polarization maintaining fiber at different lengths. The experimental results revealed the number of lasing lines increases with the increment of the polarization maintaining fiber length. The polarization maintaining fiber with 10 meters of length has the ability to generate a higher number of lasing lines up to 47 signals with semiconductor optical amplifier injected current at 180mA, respectively. However, in terms of average peak power and average optical signal to noise ratio, the 2 meter of polarization maintaining fiber length has the capability to produce a higher value which is 0.45mW at 250mA of semiconductor optical amplifier driven current and 28.86dB at 170mA of semiconductor optical amplifier driven current, respectively. Furthermore, it is observable that this configuration capable to generate a wider bandwidth which is operating in the conventional (C) band to long (L) band at the room temperature.
  • Publication
    FPGA based Quantum Key Distribution Electronic System for Multipurpose Optical Setup and Protocols
    ( 2021-03-01)
    Aseri N.S.M.
    ;
    Ali N.
    ;
    Yusof N.R.
    ;
    Endut R.
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Mohd Faidz Mohamad Shahimin
    ;
    Mohd Rashidi Che Beson
    ;
    Syed Alwee Aljunid Syed Junid
    The purpose of the FPGA electronic control system for Quantum Key Distribution (QKD) is to improve the analog electronic system in optoelectronic conversion. In the existence of the Mezzanine FPGA board, the main conversion of optical laser signal and optical detector signal can be improved. Mezzanine board can reduce the noise errors during the transmission and receiving a signal. Commonly, the optical signal needs to interface with an analog electronic system. This process requires the conversion process and interfacing with a digital signal to control the optical device and produce a good quality optical signal. The Mezzanine board can reduce the uncertainty during signal conversion and gives the digital capability to control the optical devices. The optical modulation signal for phase modulator control can achieve a full complete phase shift in the Mezzanine board. Plus, the voltage phase has capability up to 10 V with an accuracy of 2.4 µV. The time conversion for phase modulator can be extended in the Mezzanine board based on the digital control signal from FPGA. The system is capable to extend into multiple timing control to handle all the signal and to synchronize the signal in receiving, transmission or in between of the transmission. Thus, the system can handle one way or two-way QKD system accordingly.
  • Publication
    An innovative single development process for integrated optical Mach-Zehnder interferometer pattern transfer
    ( 2017-01-01)
    Nurulbariah Idris
    ;
    Lau Kuen Yao
    ;
    Kang Nan Khor
    ;
    Abdul Wahid M. H.
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Vithyacharan Retnasamy
    ;
    Mukhzeer Mohamad Shahimin
    Integrated optical Mach-Zehnder interferometer (IO-MZI) has been widely researched for various usage including for biosensor application. However, the success rate of IO-MZI pattern transfer has been low using the conventional multidevelopment process. One of the main factors is the particle contamination due to the practice of reused developer bath. In this work, an innovative single development process had been proposed with the utilization of the same conventional set-up but with a different protocol. The concept of this method is the estimation of total development time based on the calculated development rate. By doing so, the development process can be completed with only one immersion of the substrate in the developer bath. Besides, the manipulation of development rate by varying exposure time in this work also had revealed the possibility of manipulation of line-width based on the exposure time. In short, the proposed single development process has increased the success rate of IO-MZI pattern transfer from 30% (multi-development method) to 90%.
  • Publication
    Smart embedded-analytics sensors with cloud-based measurement system for HVAC
    ( 2020-01-08)
    Aseri N.S.M.
    ;
    Norshamsuri Ali @ Hasim
    ;
    Mohd Najib Mohd Yasin
    ;
    Mohd Rashidi Che Beson
    ;
    Syed Alwee Aljunid Syed Junid
    ;
    Rosdisham Endut
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Shapiai M.I.
    HVAC system is a necessary component of environment to maintain the temperature and humidity to be kept at certain levels by using air taken from outside to ensure the indoor comfort. The purpose of the study is to reduce the electricity energy usage and cost from air conditioning by using smart embedded-analytics sensors to provide the automatic thermal control in an area. In this study, we used sensors such as temperature and humidity sensors to detect and read the currently temperature and humidity of an area monitored by a microcontroller. The cloud-based system and the sensors are connected via wifi in the presence of MQTT protocol. The protocol enables publish and subscribe method which provide the communication between sensors, cloud-based system and HVAC system. This communication can serve thermal control automatically thus resulting the optimize usage of energy from air conditioning according to the external environment temperature and humidity. The control of the temperature and humidity from air conditioning can be designed through the programming embedded in the microcontroller. The monitoring result can be displayed from the control panel to ensure how the system works.
  • Publication
    Characterization of all-optical Tofolli and Peres gates employing optimized SOA-NOLM
    ( 2020-01-08)
    Nur Hafizah Ghazali
    ;
    Mohamad Halim Abd. Wahid
    ;
    Nor Azura Malini Ahmad Hambali
    ;
    Nurjuliana Juhari
    ;
    Zahari S.M.
    ;
    Shahimin M.M.
    In this work, all-optical reversible gates namely Tofolli and Peres are studied and characterized. The gates utilize semiconductor optical amplifier (SOA) in nonlinear loop optical mirror (NOLM). The reversible gates are performed at data rate 10 Gb/s with narrow Gaussian pulses as input signals. Delay of 130 ps and injection current of 170 mA have displayed the optimum outputs in the SOA-NOLM. Extinction ratio is greatly reduced, thus less noise interferes the logic operation in this simple technique. It is observed that Peres gate has shown a higher output power compare to Toffoli gate. This could be due to multiple amplification that are experienced by the signals. Other than the gain, injection current and delay are shown to give major effect in producing the correct bits at the outputs. The SOA-NOLM also can be cascaded for other arithmetic signal processing operation at high frequency. It is also recorded that the design consumes low power especially in small signal gain process. Thus, the design indicates its versatility to be executed in photonic integrated circuits for ultrafast signal control through fiber networks.