Nurjuliana Juhari
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Preferred name
Nurjuliana Juhari
Official Name
Nurjuliana, Juhari
Alternative Name
Juhari, Nurjuliana Binti
Juhari, Nurjuliana
Juhari, N.
Juhari, N. J.
Main Affiliation
Scopus Author ID
22634152000
Researcher ID
CWQ-4839-2022

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  • 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
    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.
      1  39
  • Publication
    Design of arrayed waveguide grating (AWG) demultiplexer based PMMA for narrow channel spacing
    ( 2020-01-08)
    Nurjuliana Juhari
    ;
    Yusof, Muhammad Fadzliazuan
    ;
    Mohamad Halim Abd. Wahid
    ;
    Nur Syakimah Ismail
    Arrayed Waveguide Grating (AWG) based PMMA polymer that functioning as multiplexer/demultiplexer (mux/de-mux) having good potential in WDM system and interferometer optical sensor. Besides, AWG is suitable for larger count optical signals and good filter response devices. AWG demultiplexer based polymer was simulated using Beam Propagation Method (BPM) under TE mode with 1550 nm central wavelength. This work explores the performance of polymer-based AWG with straight waveguide structure that capable to produce 16-channels AWG device for 100 GHz (0.8 nm) channel spacing. The 16-channels AWG based polymer produces low insertion loss of 3.430 dB and low crosstalk of -24.763 dB. The central wavelength for each output port gives almost similar values with the standard ITU-T DWDM wavelength grid with the smallest difference of 0.5 nm. This proposed device also capable to solve the demand on higher channel capacity especially to support internet usage and the needs of the best communication system.
      37  3
  • Publication
    Effect of heating power towards synthesis of carbon dots through microwave pyrolysis method for optical-based biosensor
    ( 2020-01-08)
    Nur Syakimah Ismail
    ;
    Husain, Umi Shahirah
    ;
    Selvan S.
    ;
    Mordani, Nor Afnia
    ;
    Nurjuliana Juhari
    ;
    Nur Hamidah Abdul Halim
    This study focuses on the effect of heating power in producing carbon dots (CDs) using microwave-assisted pyrolysis from glucose and PEG-200. Glucose is one type of saccharide that contains carbon atom in their structure while PEG-200 is a polymer that acts as a stabilizer. Synthesis of CDs was carried out by using a domestic microwave at different heating power ranging from 300 to 600 Watts. Produced CDs were subjected to dilution, filtering and dialysis procedure for purification purpose. UV-Vis was carried out using PerkinElmer Lambda 35 Spectrophotometer to prove the present of carbon dots in the sample solution. Photoluminescence intensity was observed using Horiba FluoroLog Spectrophotometer together with Horiba iHR550 Imaging Spectrometer to show the emission wavelength and the emission color of CDs prepared. UV-Vis results show the present of CDs in each sample from absorption peaks in the range between 240 nm until 260 nm. The photoluminescence testing shows the emission wavelength of prepared CDs solution is around 430 nm to 570 nm which represent emission color of green-yellow luminescence. From this experiment, CDs that were prepared using a heating power of 450 Watt in 2 minutes and went through the filtering process produce the best luminescence properties. Prepared CDs display electrochemiluminescence (ECL) properties in the presence of co-reactant potassium peroxydisulfate using cyclic voltammetry to pave the way for optical-based biosensor application.
      36  2
  • Publication
    Dyes extracted from Hibiscus Sabdariffa flower and Pandannus amaryllifolius leaf as natural dye sensitizer by using an alcohol-based solvent
    ( 2021-03-01)
    Rosli N.
    ;
    Norhayati Sabani
    ;
    Shahimin M.M.
    ;
    Nurjuliana Juhari
    ;
    Shaari S.
    ;
    Ahmad M.F.
    ;
    Zakaria N.
    The efficiency improvement of Dye sensitized solar cells (DSSC), the fabrication of DSSC by using metal-free organic natural dyes with a different type of solvents for the extraction of dye sensitizer was investigated. The metal-free organic Dye which comes from anthocyanin and chlorophyll dyes were dissolved by using different solvents, which are ethanol, methanol and mixture of ethanol and methanol. Anthocyanin dye was extracted from the petals of Hibiscus Sabdariffa (Roselle), and chlorophyll dye was extracted from the epidermal leaves of Pandannus amaryllifolius (Pandan). The purpose of using different solvents from alcohol-based was to determine which solvents that produce the highest effect in term of efficiency for DSSC. To confirm which solvents that produce the highest efficiency to the DSSC, the photovoltaic measurement was conducted, and the data was collected. From the photovoltaic analysis, the J-V characteristics under illumination are recorded. The sample that used anthocyanin dye extracted from Roselle flower diluted with methanol solvent gave the highest efficiency which is 0.0005% with the following parameters-Voc = 0.419 V, Jsc = 0.0057 mA/cm2 and FF = 0.24. Meanwhile, the sample that used chlorophyll dye extracted from Pandan leaves diluted with a mix of ethanol and methanol solvents gave the highest efficiency which is 0.00014% with the following parameters-Voc = 0.347 V, Jsc = 0.0016 mA/cm2 and FF = 0.25.
      33  2
  • Publication
    Analysis of Power Distribution in Mach Zehnder Interferometer Polymer-based Waveguide for Sensing Applications
    ( 2022-12-01)
    Mohd. Azarulsani Md. Azidin
    ;
    Nurjuliana Juhari
    ;
    Arif Mawardi Ismail
    ;
    Norhayati Sabani
    Two Mach Zehnder Interferometer (MZI) polymer-based waveguide designs namely MZI symmetrical and MZI asymmetrical structures were simulated and analyzed using Optiwave OptiBPM10. The two designs with device size of 4000μm x 300μm exhibit clear optical propagation path when light is simulated through them as well as displaying single mode profile. Highest output power was obtained by the MZI symmetrical design at 0.90 a.u, which suggests better waveguide design for sensing applications.
      1  26
  • Publication
    Modification of Photoanode Surface Structure via Image Analysis on Organic Polymer Material based for Dye-Sensitized Solar Cell (DSSC) Applications
    ( 2021-12-01)
    Nur Liyana Mohd Rosli
    ;
    Norhayati Sabani
    ;
    Mohd Fairus Ahmad
    ;
    Mohd. Azarulsani Md. Azidin
    ;
    Nurjuliana Juhari
    ;
    Nor Farhani Zakaria
    ;
    Mohd Natashah Norizan
    ;
    Safizan Shaari
    In this study, the experiment on the modification of the photoanode with organic polymer material as copolymer template for dye-sensitized solar cell (DSSC) applications has been conducted. The two organic copolymer templates are polystyrene sphere (PS) and poly[2-methoxy-5(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV). The modification photoanodes were made using Dr. Blade’s method. These organic copolymer templates were added to improve the surface of the mesoporous titanium dioxide (TiO2) layer, which is used as the main component in DSSC photoanode. The unmodified TiO2 photoanode has poor aggregation and porosity of TiO2. The addition of either MEH-PPV or PS sphere to the photoanode layer was found to affect the surface of mesoporous TiO2 in terms of porosity, particle size distribution and shape. The analysis of the TiO2 modification was conducted using an image analysis processing method via a 2D scanning electron microscope (SEM) image. The image analysis processing method used was the ImageJ program. The DSSC of modified photoanode is fabricated using metal complex dye, Ruthenium (N719) dye. The data collected from the ImageJ program showed that by adding organic copolymer templates into TiO2, the porosity of TiO2 decreased from 45 % to 42 %. From the photovoltaic analysis obtained, the J-V characteristic is recorded with the photoanode of TiO2 mixed with 1.00 wt% MEH-PPV gave the highest efficiency, which is 0.01 % with the following parameters – Voc = 0.43 V, Jsc = 0.17 mA/cm2 and FF = 0.20. Meanwhile, the photoanode of TiO2 mixed with 0.50 wt% PS sphere gave the highest efficiency which is 0.08 % with the following parameters – Voc = 0.39 V, Jsc = 0.86 mA/cm2 and FF = 0.25.
      1