Abdulhadi Al-Janabi
@uobaghdad.edu.iq
Institute of laser for postgraduate studies
University of Baghdad
Abdulhadi Al-Janabi received the Ph.D. degree from the Indian Institute of Technology, Delhi, India, in 1993. He did his postdoctoral training at the Institute of Photonics, Vienna University of Technology, Austria, in 2004. He is currently a Professor with the Institute of Laser for Postgraduate Studies, University of Baghdad, Iraq. His current research interests include fiber laser, fiber laser sensors, and photonics applications.
EDUCATION
Ph.D. Laser Physics
RESEARCH INTERESTS
Fiber lasers , optical fiber sensors , laser in dentistry , laser design , short and ultrashort laser pulses
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Shahad Sabhan Al-Lami, Hussein.K. Atea, Ansam M. Salman, and Abdulhadi Al-Janabi
Elsevier BV
Hussein Alaa Al-Rubaiyee, Sarah Kadhim Al-Hayali, Sulaiman Wadi Harun, and Abdul Hadi Al-Janabi
Elsevier BV
Sura Hussein Mahmood, Sarah Kadhim Al-Hayali, and Abdulhadi Al-Janabi
Optica Publishing Group
In this paper, we describe the first demonstration of an optical fiber sensor based on two cascaded architectures of the Mach–Zehnder interferometer (MZI) with an up-down-tapered (UDT) hetero-core fiber structure for simultaneous pH measurement at two different spatial locations. The two fiber structures, namely structures I and II, were fabricated by sandwiching a 45 mm and 60 mm long piece of no-core fiber (NCF) between two single-mode fibers (SMFs), respectively. By inserting a down-taper between two adjacent up-tapers in the NCF section using the over-fusion splicing technique, the UDT hetero-core fiber structure was achieved. The down-taper works as an optical attenuator, while the two up-tapers each function as a fiber splitter/combiner. By cascading the two sensor structures I and II, two distinct interference dips were obtained, resulting in dual sensing points (so-called sensing points I and II). According to experimental results, it was shown that the proposed sensing points I and II are pH-sensitive, and exhibit sensitivities of 1.0428 nm/pH and −1.7857nm/pH for simultaneous measurement for each point as the pH ranged from 8 to 14 and from 1 to 7 pH, respectively. The obtained results show that the proposed dual point pH sensor has the potential to be used for the simultaneous detection of pH parameters in any environment and at various places.
Sura Hussein Mahmood, Sarah Kadhim Al-Hayali, and Abdulhadi Al-Janabi
Optica Publishing Group
In this paper, we report the demonstration of an optical fiber sensor based on the cascaded up-down-tapered (UDT) hetero-core fiber structures in a sequence for simultaneous refractive index (RI) measurement at dual spatial locations for the first time. The two hetero-core fiber structures, namely sensor structures A and B, were fabricated by sandwiching a section of no-core fiber (NCF) with lengths of 45 and 60 mm between two standard single-mode fibers (SMF), respectively. The UDT hetero-core fiber structure was formed by introducing a down taper between two adjacent up tapers in the NCF section by using the over-fusion splicing method. The dual up tapers respectively serve as a fiber splitter/combiner, and the down taper acts as an optical attenuator. The proposed dual point sensing head (sensing point A and sensing point B) was engineered by cascading the two sensor structures A and B to generate two separate interference dips and achieve wavelength division multiplexing. Experimental results show that for the dual point sensing structure, sensing point A and sensing point B are sensitive to RI independently and simultaneously, and exhibit sensitivities of 99 nm/RIU and 93.7 nm/RIU for simultaneous measurement of RI ranging from 1.33 to 1.38 for each point, respectively. During measurement, there is no mutual interference to each sensing head. The results point out that the proposed dual point sensor can be potentially applied for the simultaneous detection of RI in any environment and at different locations.
Shahad Sabhan Al-Lami, Ansam M. Salman, and Abdulhadi Al-Janabi
Elsevier BV
Shahad Sabhan Al-Lami, Ansam M. Salman, and Abdulhadi Al-Janabi
Optica Publishing Group
A simply designed, highly sensitive, stretchable, compact wearable, and skin-like optical fiber sensing instrument is designed and demonstrated for joint motion monitoring. The fiber sensing scheme comprises only a section of single-mode fiber (SMF) deformed in the knot-like configuration, which performs as a Mach–Zehnder interferometer (MZI) based on a modal coupling mechanism between the core and cladding modes of the deformed SMF section. This proposed optical fiber sensor based on a knot-like configuration is mounted onto wearable woven fabric and then garments on the limbs of a healthy human’s body. As the flexion angle of the human limb is varied, the interference fringe coding based on the spectral shift difference of the periodical transmission spectra is perceived. The proposed wearable optical fiber sensor exhibits excellent sensitivities from around −0.431 to −0.614nm/∘ realized for elbow and knee joint flexion between a range of motion around 0°–90°. Additionally, this sensor also displays high repeatability and stability and a fast response time of 1.4 ms, combined with a small standard deviation of about 2.585%. The proposed sensor device possesses manufacturing simplicity, high processing accuracy, lightness, and elasticity, as well as certain improvements over other goniometers and optical fiber sensors. These attributes of the proposed sensor prove its applicability for human joint angle monitoring.
Fay F. Ridha and Abdulhadi Al-Janabi
Springer Science and Business Media LLC
Raneen KH. Al-Hamd and Abdulhadi Al-Janabi
Optica Publishing Group
This in-vitro study evaluates the efficacy of the teeth bleaching approach using different laser wavelengths (405 nm blue diode, 940 nm infrared diode, and Er,Cr:YSGG 2780 nm lasers) in comparison to the conventional method using light-emitting diode (LED) sources (420–480) nm. Eighty caries-free sound human premolars were randomly divided into four groups (N=20). Each group received a different bleaching procedure. Then each group was further subdivided into two subgroups (N=10) stained with different solutions. The pulp chamber temperature rise was recorded using an optical fiber sensor with a novel design and fabrication. The color was analyzed using a digital spectrophotometer. Five samples of each subgroup were tested for surface roughness, while the others were tested for Vickers microhardness. The bleaching process with a short wavelength 405 nm blue diode laser showed the best results for the shade, with a minimum pulpal temperature increase indicating no possible necrosis and hence maintaining tooth vitality. Additionally, a remarkable reduction in bleaching time was achieved compared to the conventional approach. This process also yielded the highest color change (ΔE) and increased microhardness, with no noticeable change to the tooth roughness. The 405 nm blue diode laser applied for bleaching showed the best bleaching activity against tested stains and negligible pulpal temperature rise with a noticeable reduction in the bleaching time. The proposed novel method to measure temperature change could be used to develop a promising smart sensor for quick, effective, repeatable, and in-situ monitoring of human body temperature.
Saif A. Mohammed, Sarah Kadhim Al-Hayali, and Abdul Hadi Al-Janabi
Optica Publishing Group
In this paper, dual-wavelength laser emission of an erbium-doped fiber laser (EDFL) with a tunable distinct wavelength selection of the simultaneously produced laser lines was achieved by applying a parallel comb filter configuration based on the optical Vernier effect. The intracavity inserted proposed comb filter consists of two parallel branches to generate the Vernier effect. Each branch is an in-line Mach–Zehnder interferometer (MZI) filter, which is composed of a polarization-maintaining fiber fusion spliced between single-mode fibers with sphere shapes at both ends. The tunability of the selected laser wavelength was realized by submerging the proposed filter in different sodium chloride/water mixtures. The proposed comb filter-based Vernier effect was used to independently achieve the selection of the dual-wavelength EDFL lines and for refractive index (RI) sensing applications. The in-line MZI1 and MZI2 structures show a wavelength shift sensitivity to RI variations of −88 and 79 nm/RIU, respectively. Our proposed MZI structure presents a reliable, straightforward, and low-cost spectral comb filter for separate tunable dual-wavelength laser generation in the c-band region. Furthermore, the proposed filter structure-based Vernier effect presents a new perspective and method in the RI sensing application.
Saif A. Mohammed, Sarah Kadhim Al-Hayali, and Abdulhadi Al-Janabi
SPIE-Intl Soc Optical Eng
Abstract. We propose and demonstrate the implementation and application of a new configuration of an all-fiber comb filter based on the Vernier effect produced by parallel-connected two in-line Mach–Zehnder interferometers (MZIs). Each in-line MZI was fabricated by fusion splicing a section of panda-type polarization maintaining fiber (PMF) with peanut-shaped tapers between two single-mode fibers. These two in-line MZIs, respectively, form reference and sensing interferometers, which are parallel-connected by two 3-dB optical fiber couplers to realize the Vernier effect. By incorporating the proposed comb-filter into the erbium-doped fiber laser cavity, two output channels at 1533.2 and 1558.2 nm have been achieved. Further, the combination of the parallel-connected two in-line MZIs and polarization controllers (PC1 and PC2) promotes the lasing in a switchable and selective way. To the best of the authors’ knowledge, this is the first demonstration of a comb filter that employs paralleled two peanut-shaped MZIs in PMF. The experimental results indicate that the proposed filter has the potential to be used in communication systems.
Hussein Alaa Al-Rubaiyee, Sarah Kadhim Al-Hayali, and Abdul Hadi Al-Janabi
Optica Publishing Group
In optical communications systems, the used filter and/or demultiplexer needs to have a broad free spectral range (FSR) in order to accommodate more channels and have acceptable interchannel crosstalk. The Vernier effect applied to fiber filters is a recent effective tool to enlarge the FSR. Here, by harnessing the Vernier effect of a hybrid interferometer consisting of a Mach–Zehnder interferometer (MZI) and Sagnac interferometer (SI), we proposed and experimentally demonstrated a new kind of comb filter for a switchable and interval adjustable multi-wavelength C-band erbium-doped fiber laser (EDFL) application. In the designed comb filter, the MZI is composed of bi-tapered polarization-maintaining fibers (PMFs) fabricated by fusion splicing and has the function of achieving the switchability of the proposed dual-wavelength EDFL. The SI configured by nesting tapered PMF is employed as a switchable and wavelength-spacing tuning component of triple-wavelength EDFL. In this experiment, the FSR of the MZI and the SI is designed to be close but not equal, which could be achieved by properly adjusting the length of the employed PMF, so the Vernier effect can exist and a comb spectrum with an obvious envelope is obtained. Through the adjustment of the polarization controller (PC1) and (PC2) inside the cavity, a switchable and interval-adjustable multi-wavelength EDFL was achieved. To the best of the authors’ knowledge, this is the first time that an all-fiber hybrid filter based on the Vernier effect has been used to manipulate the spectral output characteristic of an EDFL and achieve a switchable multi-wavelength fiber laser.
Ayat salam, Rawaa A. Faris, and Abdulhadi Al-janabi
Optica Publishing Group
We report on using a CO2 (10.6 µm) laser to debond the lithium disilicate veneers. Sixty-four sound human premolar teeth and 64 veneer specimens were used in the study. The zigzag movement via CO2 laser handpiece along with an air-cooled jet to prevent temperature elevation above the necrosis temperature limit (5.5 C°) was applied. The optimal deboning irradiation time was super-fast, at about 5 seconds at 3 Watt CO2 laser power. It is 20 times less than any previously published work for veneers debonding. The enamel beneath the debonded veneers has been assessed by atomic force microscopy (AFM) and shear stress technique as criteria for the easiness of debonding. The fast deboning process with nonsignificant changes in enamel integrity and tooth vitality reflects the high potential of CO2 laser in veneers debonding.
Alyamama MH. Al-Shammari, Ansam M. Salman, and Abdulhadi Al-janabi
Optica Publishing Group
In this in-vitro study, a gradient-in-power approach aims to ensure no temperature elevation beyond the necrosis limit (5.5 °C) during laser cavity preparation of dental hard tissues. The applied optimal Er,Cr:YSGG laser parameters were: 20 Hz pulse repetition rates (prr), average powers at a maximum of 5.5 W for enamel switched to a maximum of 3.5 W for dentine surface specimens. A fabricated fast-response all-optical fiber sensor was used to monitor temperature change simultaneously. A scanning electron microscope (SEM) and a Fourier transform infrared (FTIR) spectroscopy were used to assess the irradiated surfaces. Holes of 500 µm in depth were obtained with no morphological and chemical alterations.
Shahad Sabhan Al-Lami, Ansam M. Salman, and Abdulhadi Al-Janabi
Optica Publishing Group
This work presents a wearable optical fiber sensing scheme based on an eight-figure macro-bend fiber configuration. The wearable sensor scheme utilizes a single-mode fiber deformed on an eight-figure configuration. The fabricated optical fiber sensor is mounted onto a wearable woven fabric and then garment on the elbow and knee joints of different healthy volunteers’ bodies. The proposed wearable biomechanical sensor shows an excellent sensitivity correlated with the human knee and elbow joints’ range of motion 0°-90° which is about −0.963 nm/°, with good regression coefficients (R2) exceeding 99.6%, for elbow joint flexion and sensitivity of 0.874 nm/° with a high R2 exceeding 99.4% for knee flexion. Besides, this sensor also displays high repeatability and stability and a fast response time of 1.66 ms, combined with a small standard deviation of about 2.321%. So, the planned wearable optical fiber sensor system is a practicable option for monitoring joint motion, human movement analysis, and soft robots.
Ansam M. Salman, Sarah Kadhim Al-Hayali, and Abdul Hadi Al-Janabi
Optica Publishing Group
Construction of pH sensors based on optical fiber encapsulated copper (Cu-NPs) has been accomplished. Briefly, a length of single-mode fiber (SMF) of about 25 cm has been wrapped in two rings by twisting one side of the fiber on the other from both ends to form a figure-eight shape. To upsurge the sensitivity, the sensor configuration has been immobilized with copper nanoparticles/polyvinyl alcohol hydrogel (Cu/PVA) composite. The Cu/PVA composite was employed to shape a membrane structure on the sensing active length by laminating it using the dip-coating method. The wavelength interrogation method was employed to evaluate the sensitivity of the fabricated pH sensor. The fabricated fiber pH sensor exhibits a sigmoidal response above a wide range of pH from 1 to 14. The result displays a superior sensitivity of ∼4.8 nm/pH for a range of 1-7 pH and 3.86 nm/pH for the range of 8-14 pH with an excellent linear response. Besides the great sensitivity, the dual-parameters measurement of pH and refractive index was effectively accomplished with perfect stability. The proposed fiber sensor possesses a superior performance compared with the other sensors.
Ali H.Abdulhadi and Abdulhadi Al-Janabi
Optik Elsevier BV
Fay F. Ridha, Abdulhadi Al-Janabi, and Sarah Kadhim Al-Hayali
Applied Optics Optica Publishing Group
Ansam M. Salman, Rawaa A. Faris, and Abdulhadi Al-Janabi
Elsevier BV
M. Al-Rubaiee, A. H. Al-Janabi, S. C. Fleming, and A. Argyros
Journal of the European Optical Society-Rapid Publications Springer Science and Business Media LLC
AbstractOne of the unique properties of metamaterials is the ability to manipulate electromagnetic waves at subwavelength scales, made possible by their structure on these scales. Here, rather than consider effective bulk properties, we consider the properties of microscopic features based on considering resonant unit cells. We used wire array metamaterials to form localized resonant cavities by changing the resonance frequency of one or more unit cells, surrounded by unchanged unit cells that do not support resonance for the propagating mode (i.e. forming a band gap). We validate our approach experimentally with electromagnetic waves in the terahertz range, demonstrating and characterizing subwavelength resonant cavities in this range. These resonant cavities can pave the way for ultra-compact subwavelength waveguides and other optical components.
Ansam M. Salman, Sarah Kadhim Al-Hayali, and Abdulhadi Al-Janabi
Institute of Electrical and Electronics Engineers (IEEE)
Ansam M. Salman, Sarah Kadhim Al-Hayali, Rawaa A. Faris, and Abdulhadi Al-Janabi
Optik Elsevier BV
Haneen Qassim Merza, Sarah Kadhim Al-Hayali, and Abdul Hadi Al-Janabi
Optics Communications Elsevier BV
Haneen Qassim Merza, Sarah Kadhim Al-Hayali, and Abdul Hadi Al-Janabi
Infrared Physics and Technology Elsevier BV
Zahraa J. Naeem, Ansam M. Salman, Rawaa A. Faris, and Abdulhadi Al-Janabi
Applied Optics The Optical Society
Fay F. Ridha, Ansam M. Salman, and Abdulhadi Al-Janabi
Applied Optics The Optical Society