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
Rapid using an uncoated optical fiber-based Mach-Zehnder interferometer salivary pH sensor Hamsa Radhwan Tawfeeq, Abdulhadi Al-Janabi Optics Continuum, 2026 In this study, an uncoated optical fiber–based Mach–Zehnder interferometer (SMF–NCF–SMF) salivary pH sensor is developed and experimentally evaluated as a rapid, non-invasive diagnostic tool for gingivitis screening. The sensor exploits multimode interference and refractive index sensitivity, enabling wavelength-shift demodulation of pH-induced spectral changes in saliva. Clinical validation was performed on 83 individuals, of whom 38 exhibited clinically healthy gingiva, and 37 were diagnosed with gingivitis. The proposed sensing structure demonstrated a sensitivity of 1.5 nm/pH and strong linearity exceeding 98%, with gingivitis patients exhibiting significantly more alkaline salivary conditions compared with healthy subjects (p < 0.001). To further support diagnostic reliability, salivary IL-1β levels were quantified using ELISA, revealing elevated concentrations in gingivitis cases and reinforcing the association between salivary biochemical changes and inflammatory periodontal status. The presented optical fiber sensor exhibits high stability, rapid response, and clinical feasibility, highlighting its potential as a practical chairside screening tool for early gingivitis detection.
Reconfigurable multiwavelength Er-doped fiber laser based on free spectral range control of parallel connected nonlinear photonic crystal fiber Mach-Zehnder interferometers Ali Salah Mahdi, Sarah Kadhim Al-Hayali, Abdulhadi Al-Janabi Optical Engineering, 2025 We experimentally demonstrated a new parallel filter configuration based on a couple of Mach–Zehnder interferometers (MZIs) for reconfigurable multiwavelength Erbium-doped fiber laser (EDFL). The parallel filter comprises two arms fabricated by cascading two optical couplers (OCs). One arm is an in-line MZI (MZI-1) composed of a section of non-linear photonic crystal fiber (NLPCF) spliced between two single-mode fibers (SMFs), which can serve as a selector of the lasing wavelength in the proposed ring laser cavity. The other arm is an in-line MZI (MZI-2) constructed by a core-offset fusion splicing of a section of NLPCF between two SMFs, which can adjust the wavelength spacing of the multiwavelength laser. The free spectral range (FSR) is contingent upon the difference in the optical path between the two arms of the proposed filter structure. Consequently, employing the offset technology to splice the NLPCF allowed the regulation of the optical path difference between the two arms of the MZI. The two MZIs, arranged as parallel filters, were initially employed as transmission spectral filters for the concurrent generation of dual-wavelength in EDFL at 1530.6 and 1528.2 nm. Furthermore, the change in the spectra of the proposed filter via the adjustments of the polarization controllers (PCs) states was examined. Changing the PC1 state within the cavity alters the FSR of the parallel filter, enabling the attainment of switchable single, dual, and triple wavelengths. Subsequently, by altering the PC-2 integrated into the arm of the MZI-2, the FSR of the MZI-2 can be adjusted, thereby varying the wavelength interval from 1.0 to 3.0 nm. The results suggest that the proposed filter could be a promising approach for stable switchable and adjustable multiwavelength laser generation with potential applications in optical communications and sensing.
Zero and double-knotted droplet-shaped optical fiber sensor for rapid temperature variation monitoring Ansam M. Salman, Abdulhadi Al-Janabi, Zainab M. Salman, Karrar M. Salman, Shahad Sabhan Al-Lami Optics Continuum, 2024 Compact, simple optical fiber sensors based on a macro-bend fiber configuration were fabricated and proposed for instantaneous temperature measurement. These fiber sensors were manufactured by straightforwardly mechanically bending two different pieces of single-mode fiber (SMF) into zero-knotted droplet-shaped and double-knotted droplet-shaped, separately, with radii of a few millimeters. The sharp bending excites mode interferences among the core mode and the stimulated modes transmitting in the cladding region of the silica SMF. Many resonant interference fringes were perceived in the transmission signal and were noticed to shift to a shorter spectral region with the rise of environmental temperature (ET). The resultant data prove the practicality of the fabricated optical fiber sensors with excellent temperature sensitivities of about −1.128 nm/°C and −1.904 nm/°C, for zero-knotted droplet-shaped and double-knotted droplet-shaped, respectively, which is several times larger than sensors based on straight-transmitted fiber constructions. The proposed sensors’ structures may contribute effectively to temperature variations monitoring for environmental or industrial uses due to their large thermo-optical coefficient of the silica core and the big RI difference between the core and cladding of the bending fiber section.
Subwavelength imaging and cavities using wire array fibres Alexander Argyros, Jessienta Anthony, Xiaoli Tang, Mohanad Jamal, A. Hadi Al-Janabi, Simon C. Fleming, Boris T. Kuhlmey Asia Communications and Photonics Conference Acpc 2015, 2015
Wire arrays fabricated by drawing for THz and IR metamaterials Alexander Argyros, Osama T. Naman, Alessandro Tuniz, A. Hadi Al-Janabi, Matthew R. New-Tolley, Inna Karatchevtseva, Simon C. Fleming, Boris T. Kuhlmey International Conference on Infrared Millimeter and Terahertz Waves Irmmw Thz, 2012
Changes in ovarian function associated with oxytocin injection to immature rats Annales De Recherches Veterinaires, 1987
RECENT SCHOLAR PUBLICATIONS
Erbium fiber ring laser and conventional demodulation techniques for salt concentration detection based on a hetero core optical fiber sensor W Mhmood Khudhair, SK Al-Hayali, A Al-Janabi Optics Continuum 5 (4), 1155-1169 , 2026 2026
All-fiber sucrose concentration sensor incorporating a hetero-core MZI as a spectral filter in an EDFL cavity WM Khudhair, A Al-Janabi, SK Al-Hayali Optik, 172701 , 2026 2026 Citations: 1
Rapid and non-invasive diagnosis of gingivitis using an uncoated optical fiber-based Mach-Zehnder interferometer salivary pH sensor HR Tawfeeq, A Al-Janabi Optics Continuum 5 (2), 365-378 , 2026 2026
Compact high-sensitive Mach-Zehnder-based optical fiber sensor for monitoring gaseous acetone concentrations YH Kadhum, AM Salman, A Al-Janabi Optical Fiber Technology 95, 104422 , 2025 2025 Citations: 3
Numerical optimization and performance evaluation of Pr3+/Yb3+doped all-fiber up-conversion visible fiber laser AHAJ Ali Salah Mahdi*, Wijdan Mhmood Khudhair, Sarah Kadhim Al-Hayali Optical Fiber Technology 90, 104119 , 2025 2025 Citations: 3
No Core-Thin Core-No Core Optical Fiber Sensor Based MZI for in Time Detection of Bovine Serum Albumin WM Khudhair, SK Al-Hayali, A Al-Janabi Sensing and Imaging 26 (1), 89 , 2025 2025 Citations: 5
A drop-like optical fiber salivary pH sensor: A rapid and real-time detection of periodontal disease HA Sabbar, SK Al-Hayali, A Al-Janabi Analytical Biochemistry 701, 115818 , 2025 2025 Citations: 9
Spacing adjustable and switchable multi-wavelength Erbium-doped fiber laser based on the parallel filter of photonic crystal fibers and polarization hole burning effect AAJ Ali Salah Mahdi , Sarah Kadhim Al-Hayali Infrared Physics and Technology 147, 105814 , 2025 2025 Citations: 5
Wearable Textile: A Drop‑Shaped Optical Fiber Sensor Based on Hybrid Integration of Wavelength and Intensity Modulation for Human Body Motion Monitoring HKASSALAMSAA Janabi3 Sensing and Imaging 26 (37) , 2025 2025 Citations: 8
Reconfigurable multiwavelength Er-doped fiber laser based on free spectral range control of parallel connected nonlinear photonic crystal fiber Mach–Zehnder interferometers AHAJ Ali Salah Mahdi,, Sarah Kadhim Al-Hayali Optical engineering 64 (2), 026102-1 , 2025 2025 Citations: 3
Zero and double-knotted droplet-shaped optical fiber sensor for rapid temperature variation monitoring SSAL Ansam M. Salman, Abdulhadi Al-Janabi, Zainab M. Salman, Karrar M. Salman Optics Continuum 3 (12), 2360-2368 , 2024 2024 Citations: 9
Tapered coreless optical fiber-based refractive index sensor for acetone concentration detection YH Kadhum, AM Salman, A Al-Janabi Optics Continuum 3 (11), 2127-2138 , 2024 2024 Citations: 11
Adjustable optical fiber displacement-curvature sensor based on macro-bending losses with a coding of optical signal intensity SS Al-Lami, HK Atea, AM Salman, A Al-Janabi Sensors and Actuators A: Physical 373, 115403 , 2024 2024 Citations: 26
Vernier effect based on cascading two Mach–Zehnder interferometers for selectable comb filter and saturable absorber applications in erbium-doped fiber laser HA Al-Rubaiyee, SK Al-Hayali, SW Harun, AH Al-Janabi Optical Fiber Technology 84, 103757 , 2024 2024 Citations: 9
Wide-range pH sensor based on a cascaded MZI up-down tapered hetero-core structure S Hussein Mahmood, S Kadhim Al-Hayali, A Al-Janabi Applied Optics 63 (11), 2906-2915 , 2024 2024 Citations: 11
Switchable mode-locked ytterbium-doped fiber laser based on macrobending loss tuning of figure-eight knot fiber structure AMS Abdulhadi Al-Janabi , Haneen Qassim Merza,, Sarah Kadhim Al-Hayali Optical engineering 63 (4), 046104-1 046104-13 , 2024 2024 Citations: 5
Wide-range pH sensor based on cascaded MZI up-down tapered hetero-core structured S Hussein, SK Al-Hayali, A Al-Janabi Optica Open , 2023 2023
Multiplexed dual-point refractive index sensor based on cascaded up-down tapered hetero-core structured fiber ANDAALJ SURA HUSSEIN MAHMOOD, SARAH KADHIM AL-HAYALI Optics Continuum 2 (12), 2451-2467 , 2023 2023 Citations: 7
Skin-like and highly elastic optical fiber strain sensor based on a knot-bend shape for human motion monitoring AAJ shahad al lami, Ansam Salman Applied Optics 62 (33), 8958-8967 , 2023 2023 Citations: 15
Copper oxide nanomaterial saturable absorber as a new passive Q-switcher in erbium-doped fiber laser ring cavity configuration SA Sadeq, SK Al-Hayali, SW Harun, A Al-Janabi Results in Physics 10, 264-269 , 2018 2018 Citations: 63
High sensitivity balloon-like interferometric optical fiber humidity sensor based on tuning gold nanoparticles coating thickness SK Al-Hayali, AM Salman, AH Al-Janabi Measurement 170, 108703 , 2021 2021 Citations: 59
Ultrashort pulse generation with an erbium-doped fiber laser ring cavity based on a copper oxide saturable absorber AHAJ Sinan Abdulhameed Sadeq, Sulaiman Wadi Harun Applied Optics 57 (18), 5180-5185 , 2018 2018 Citations: 58
High sensitivity balloon-like thermometric sensor based on bent single mode fiber DI Al-Janabi, A Salman, AH Al-Janabi Measurement Science and Technology 31, 115106 , 2020 2020 Citations: 49
Effect of hygroscopic polymer-coatings on the performance of relative humidity sensor based on macro-bend single-mode fiber AMSAHAJ Sarah Kadhim Al-Hayali Optical Fiber Technology 62, 102460 , 2021 2021 Citations: 46
Indefinite Media Based on Wire Array Metamaterials for the THz and Mid‐IR OT Naman, MR New‐Tolley, R Lwin, A Tuniz, AH Al‐Janabi, ... Advanced Optical Materials 1 (12), 971-977 , 2013 2013 Citations: 42
Tunable Q-switched erbium doped fiber laser based on metal transition oxide saturable absorber and refractive index characteristic of multimode interference effects DZ Mohammed, WA Khaleel, AH Al-Janabi Optics & Laser Technology 97, 106-110 , 2017 2017 Citations: 40
Synthesis and characterization of 3D-printed functionally graded porous titanium alloy A Hindy, F Farahmand, F Pourdanesh, M Torshabi, AH Al Janabi, ... Journal of Materials Science 55, 9082-9094 , 2020 2020 Citations: 39
Efficient humidity sensor based on an etched no-core fiber coated with copper oxide nanoparticles HASKAHA Al-Janabi Journal of Nanophotonics 12 (4), 046018-1 -12 , 2018 2018 Citations: 34
Erbium-doped fiber ring laser with wavelength selective filter based on non-linear photonic crystal fiber Mach–Zehnder interferometer WA Khaleel, AH Al-Janabi Laser Physics 27 (10), 105104 , 2017 2017 Citations: 33
Dual-wavelength passively Q -switched ytterbium-doped fiber laser using Fe 3 O 4 -nanoparticle saturable absorber and intracavity polarization SKM Al-Hayali, AH Al-Janabi Laser Physics 28 (3), 035103 , 2018 2018 Citations: 32
Au coated ZnO/MWCNTs nanocomposites film-induced four-wave-mixing effect for multi-wavelength generation in erbium-doped fiber laser SKAHAHAJ lRawaa A.Faris Optics communications 485 (126746) , 2021 2021 Citations: 30
Stable L-band multiwavelength erbium-doped fiber laser based on four-wave mixing using nickel nanofluid ANDAALJ ANSAM M. SALMAN,* ALI A. SALMAN Applied Optics 58 (22), 6136-6143 , 2019 2019 Citations: 29
Aluminum nanoparticles saturable absorber as a passive Q -switcher for erbium-doped fiber laser ring cavity configuration AA Salman, AH Al-Janabi Laser Physics 29 (4), 045102 , 2019 2019 Citations: 29
Sensitivity-Enhanced Moisture Sensor Based on ɵ-shape Bending Fiber Coated with Copper-Polyvinyl Alcohol Thin Film AM Salman, SKAHA Al-Janabi IEEE Sensors Journal 21 (19), 21546-21554 , 2021 2021 Citations: 28
Adjustable optical fiber displacement-curvature sensor based on macro-bending losses with a coding of optical signal intensity SS Al-Lami, HK Atea, AM Salman, A Al-Janabi Sensors and Actuators A: Physical 373, 115403 , 2024 2024 Citations: 26
Effect of graphene nanoparticle coating on the detection performance of cladding etched no-core fiber interferometer sensor for relative humidity measurement SKAHAH Al-Janabi Optical fiber technology 55, 102154 , 2020 2020 Citations: 26