Introduce
Pankaj Kumar Choudhury’s academic life was spent in different institutions in Varanasi (India). He started research career 
in 1989 from the Department of Applied Physics, Institute of Technology (IT), Banaras Hindu University (BHU, Varanasi), and received a Ph.D. degree in 1992. From 1992 to 1997, he worked as a Research Associate at the Department of Electronics Engineering (IT, BHU). Also, during 1995–1996, he was a Guest Lecturer in Physics at the Faculty of Science and Technology, Mahatma Gandhi Kashi Vidyapith (Varanasi). In 1997, he joined the Department of Physics, Goa University (Goa, India) as a Lecturer, where he was for a couple of years until the mid 1999. In 1999, he became a Researcher at the Center of Optics, Photonics and Lasers (COPL), Laval University (Quebec, Canada), where he worked on the fabrication and characterization of ferroelectric optical waveguides. During 2000–2003, he was a Researcher at the Faculty of Engineering, Gunma University (Kiryu, Japan), where he worked on the electromagnetic behavior of complex-structured optical waveguides and sensing. In May 2003, he received the position of Professor at the Faculty of Engineering, Multimedia University (Cyberjaya, Malaysia) where he was until late 2009. During the span, he also served the Telekom Research and Development (TMR&D, Malaysia) as a consultant for projects on optical devices. In 2009, he became Professor at the Institute of Microengineering and Nanoelectronics (IMEN), Universiti Kebangsaan Malaysia (The National University of Malaysia, Malaysia).
His current research interests lie in the theory of optical waveguides, which include complex mediums, fiber and integrated optics, fiber optic devices, optical sensors and metamaterial properties. He has published over 260 research papers in peer-reviewed international journals and conference proceedings; contributed chapters to 18 research level books; edited and co-edited 08 research level books in these areas.
He is the reviewer for nearly four dozen research journals. Also, he serves the Editorial Board of International Journal of Humanitarian Technology (Inderscience Publishers, Switzerland). He is the Section Editor of Optik – International Journal for Light and Electron Optics (Elsevier, The Netherlands) and the Editor-in-Chief of the Journal of Electromagnetic Waves and Applications (Taylor & Francis, UK).
He is a Fellow of the Institution of Engineering and Technology (IET, UK) and the Society of Photo-Optical and Instrumentation Engineers (SPIE, USA), and a Senior Member of the Institute of Electrical and Electronics Engineers (IEEE, USA) and Optica (formerly OSA, USA). Also, he is a Traveling Lecturer of Optica.
Education&Career Profile
· Bachelor’s (1985) : Physics, Chemistry & Mathematics; Gorakhpur University (Gorakhpur, India).
· Master’s (1987) :Physics (Electronics); Gorakhpur University (Gorakhpur, India).
· Doctorate (1992) : Physics (Fiber Optics and Optical Waveguides); Avadh University (Faizabad, India).
· U. G. Diploma in German Language (1996) :Banaras Hindu University (Varanasi, India).
· November 1992 – June 1997 :Research Associate; Department of Electronics Engineering, Institute of Technology, Banaras Hindu University (Varanasi 221 005, India).
· December 1995 – November 1996 : Guest Lecturer; Faculty of Science & Technology, Mahatma Gandhi Kashi Vidyapith (Varanasi 221 002, India).
· June 1997 – June 1999 :Lecturer; Department of Physics, Goa University (Taleigao Plateau, Goa 403 206, India).
· November 1999 – July 2000 :Researcher; Center of Optics, Photonics and Lasers (COPL), Laval University (Quebec City, G1K 7P4, Quebec, Canada).
· August 2000 – March 2003 :Researcher; Satellite Venture Business Laboratory (SVBL), Gunma University (1-5-1 Tenjin-cho, Kiryu 376-8515, Gunma, Japan).
· May 2003 – December 2009 :Professor; Faculty of Engineering, Multimedia University (Jalan Multimedia, 63100 Cyberjaya, Selangor, Malaysia).
· November 2009 – :Professor; Institute of Microengineering & Nanoelectronics, Universiti Kebangsaan Malaysia (The National University of Malaysia; UKM Bangi, 43600 Selangor, Malaysia).
Research Profile
· Ph. D. Thesis :A study of the propagation of electromagnetic waves with special reference to some new types of optical waveguides and devices.
· Research Experience : 30 (Thirty) years.
· Research Interests :Complex optical mediums, Electromagnetics of micro- and nanoengineered structures, Metamaterial-based absorbers and filters, Surface plasmonics, Graphene mediums, Perovskite structures, Phase change mediums, Optical sensors, Photonic crystals.
· Theoretical Skills :Worked extensively on the electromagnetic problems related to the propagation characteristics of optical waveguides having various forms of cross-sectional geometries and/or comprised of different kinds of engineered mediums.
· Experimental Skills : Experimental techniques ranging from X-ray diffraction and photoelectron spectroscopy, scanning electron microscopy, NMR spectroscopy, etc. used for the determination of structural and optical characterization of materials fabricated by metallorganic chemical decomposition (MOD), sol-gel, thermal and e-beam evaporation routes.
· Preliminary acquaintance with the clean room techniques.
· Well acquainted with the experimental techniques involved in fiber-optic evanescent wave sensing technology.
· TKR configurations used in optical sensing.
· Novel Technologies Developed :
o Narrow-band-pass infrared optical filter.
o Optical sensor with enhanced sensitivity for the study of chemical kinetics.
o Helical clad guides for dispersion control.
o Liquid crystal-based guides with enhanced sensitivity.
o Sensitivity control in liquid-crystal based guides loaded with conducting sheath and tape helix structures.
o Chiro-ferrite and chiral nihility mediums for dispersion compensation in communication systems.
o Hyperbolic and fractal metamaterials for wide-band absorption.
o Graphene-based structures for wide-band THz filtering.
· Innovative Work :
o Introduced the parabolic cylindrical dielectric and chiral waveguides.
o Designed narrow-band-pass infrared optical filter as a monochromating device.
o Developed chemical sensor with enhanced sensitivity for the study of chemical kinetics.
o Designed oxide-confined VCSEL to be operated at 850 nm.
o Introduced chiral nihility-based planar optical waveguides for dispersion compensation.
o Investigated the DB medium-based optical guides for sensing.
o Introduced conducting sheath and tape helix loaded liquid crystal optical fibers for optical sensing.
o Worked on graphene-based structure for slow-light propagation.
o Investigated hyperbolic metamaterials for absorber- and/or filter-based photonics applications.
o Studied wide-band fractal metamaterials for visible light absorption.
· Collaborations :
o Department of Engineering Science and Mechanics, Pennsylvania State University, University Park, PA 16802-6812, USA.
o Institute for Quantum Science and Engineering, Texas A&M University, College Station, Texas 77843, USA.
o Center for Quantum Devices, Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208, USA.
o International Research Center for Advanced Photonics, Zhejiang University, CHINA.
o Department of Electronic and Computer Engineering, University of Limerick, V94 T9PX, IRELAND.
o Centre for Precision Engineering, Materials and Manufacturing Research, Institute of Technology, Sligo F91 YW50, IRELAND.
o Department of Engineering Science, University of Oxford, Park Road, Oxford OX1 3PJ, UNITED KINGDOM.
o Graduate School of Engineering, Faculty of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8530, JAPAN.
o School of Physical & Mathematical Sciences, Nanyang Technological University, 637371 SINGAPORE.
o The Energy and Resources Institute, Darbari Seth Block, India Habitat Centre, Lodhi Road, New Delhi, INDIA.
o Department of Physics, University College of Engineering, Anna University, Ramanathapuram 623513, INDIA.
o Department of Physics, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, INDIA.
o Laser and Plasma Research Institute, Shahid Beheshti University, Daneshju Blvd., Evin, Tehran 19839 69411, IRAN.
o Department of Electrical Engineering, COMSATS Institute of Information Technology, Sahiwal 57000, PAKISTAN.
o Department of Electronics, Quaid-i-Azam University, Islamabad 45320, PAKISTAN.
o Faculty of Electrical Engineering, Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi 23640, PAKISTAN.
o Department of Electrical and Electronics Engineering, Iskenderun Technical University, Hatay 31200, TURKEY.
o Department of Electrical and Electronics Engineering, Middle East Technical University – Northern Cyprus Campus, Kalkanli, Guzelyurt, TRNC/Mersin 10, TURKEY.
o School of Physics, Faculty of Applied Sciences, University Technology MARA, 40450 Shah Alam, Selangor, MALAYSIA.
· On the Research Work :
o Analytical investigations have been made of different types of optical waveguides that include guides with parabolic cylindrical, triangular, Piet Hein, annular cross-sections etc. Tapered and multilayered deformed guides have also been studied. Some of these structures have been studied with chiral materials filled inside. Apart from these, guides with chiral nihility mediums are also touched upon in the context of scattering and/or dispersion compensating properties.
o Ferroelectric thin films have been of great importance owing to the hysteresis behavior, faster switching speeds and lower operating voltages. Particularly, BaTiO3 shows ferroelectric behavior in a wide range of temperature. Using the MOD technique, thin films of BaTiO3 have been fabricated on magnesium oxide and silicon substrates with fairly good surface morphologies. Experimental techniques ranging from thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) have been used for the characterization of materials and/or thin films.
o Demonstrations have been made of the use of fiber optic sensors (FOSs) for the measurement of chemical reaction rates. The use of simple FOSs for monitoring time-dependent chemical reactions has been presented. Apart from these, studies related to the estimation of chlorine in drinking water, and the response of FOSs to dyes with varying pH/concentration have also been performed.
o One of the possible and prominent applications of periodic multilayered mediums would be in the area of optical filters. Within the context, omniguiding fibers have been studied in respect of their field and power patterns exploiting the theory of Bloch formulation.
o New kind of VCSEL structure has been investigated with 850 nm operating wavelength. The efficacy of the device lies in the introduction of the oxide layer in order to achieve a better confinement of light in the central region (of the device). Further, the introduction of low-doped DBR layers near the spacers, and the barrier reduction layers in the DBRs finally present much better efficiency. Fabrication of these has been realized, followed by the comparison of the experimental and simulation-based results.
o The use of helix structures is common in traveling wave tubes (TWTs) for the generation of microwaves. Pivoting to this concept, studies of EM wave propagation through dielectric cylindrical as well as elliptical fibers with conducting helical windings have been made considering the slow- as well as fast-wave approximations. Study has also been extended to the cases of tapered fibers, helical clad chiral fibers as well as fibers embedded with conducting tape helix structures.
o Experimental investigations have been made of the performance characteristics of erbium-doped fiber amplifiers (EDFAs) under different design configurations. Estimations have been made of gain and noise figure in different EDFA configurations. Tunable band-pass filters have been used to eliminate this unwanted noise.
o Nanophotonic waveguidance has been an important aspect of quantum networks consisting of quantum nodes and communication channels. The overall framework of waveguidance in the nanophotonic world essentially involves transmit and receive nodes, and a transmission medium for qubit transport. An enhanced framework for the construction of photonic crystal fiber (PCF) based nanophotonic waveguidance system has been proposed, and a comprehensive implementation scheme, in order to realize the proposed framework as a computer programmable model, has been presented, followed by the development of simulation platform to study the system behavior.
o Numerical modeling has been presented for four-channel nonlinear directional coupler, based on the non-classical properties of light and nonlinear Kerr effect. It has been found that the system remains of prudent use for squeezed light source. The results reported that the cavity-assisted multichannel system exhibits enhanced squeezing both in single- and compound-modes. This opens up the possibilities for the development of multichannel system as an efficient source of quantum-light generator.
o Liquid crystal optical fibers exhibit polarization anisotropy, which makes them of much technological interest and useful in many applications. Considering such aspects, studies have been made to examine the propagation behavior of liquid crystal clad optical fibers. Apart from this, an amalgamation of taper structure and clad anisotropy has also been considered. Such studies have been extended to the cases of fibers with conducting sheath as well as tape helical windings, wherein the orientation of helix structure essentially plays determining role to govern the dispersion and power confinement features of the guide.
o Metamaterials exhibit exotic electromagnetic characteristics. Studies have been made of such microstructured mediums with different forms of complexities introduced. In this stream, chiral and/or uniaxial anisotropic chiral mediums have been considered with different types of loadings on waveguides, e.g., perfect electric conductors (PEC), perfect magnetic conductors (PMC) and perfect electromagnetic conductors (PEMC). The implementations of chiral nihility mediums as well as the newly developed DB boundary conditions have also been touched upon.
o In the context of complex optical mediums, columnar and sculptured thin films have been of special mention as the waveguides comprised of such mediums may sustain surface waves at the interface, which may undergo plasmonic effects. Apart from these, multilayer waveguides would also support surface plasmonic waves, the effects on which due to measurands are greatly exploited in chemical and/or bio-sensing reasons. Investigations have been made in the relevant area with emphasis on the sensing characteristics of these complex optical nanostructured mediums.
o To overcome the issue of pulse broadening in optical communication systems, schemes/devices have been investigated to exhibit high group velocity dispersion (GVD) that is useful in gaining control over dispersion. Within the context, chiral mediums exhibit magnetoelectric coupling, and also, possess unique features of optical activity and circular dichroism. It has been found that chiral nihility mediums may be used to devise dispersion compensator. Furthermore, chiroferrite guides have also been investigated with focus on the possible usage in dispersion compensation.
o The tailor-made metamaterials can exhibit many exotic properties, which can be used for our daily life applications. In this context, metamaterial absorbers can be developed implementing the nanotechnology-based tools, and can be of many usages, viz. thermal switching, wireless power transmitters, EM heating devices, solar cells, etc. In view of technological potency, attempts have been made to study a few varieties of these to improve the absorptivity. Furthermore, hyperbolic metamaterials exploiting the usage of gold and/or silver nanorods have also been investigated for absorber- and/or filter-based photonics applications.
o In view of graphene being one of the most eco-friendly candidates, varieties of graphene- and graphite-based structures have been investigated to demonstrate optical filtering and/or sensing characteristics. Also, these would prove potentials in optical on-chip communications where the delay in optical signals remains vital. The use of graphene along with phase change mediums, such as VO2, GST and SrTiO3, has also been of great importance in achieving suitable bias for temperature sensing devices. Such studies have been reported with emphasis on the tuning features.
Professional Activities/Achievements
· Traveling Lecturer; Optica (formerly OSA).
· Editor-in-Chief (2013 – contd.);Journal of Electromagnetic Waves and Applications (ISSN: 0920-5071 (Print), 1569-3937 (Online); Published by Taylor & Francis Ltd., United Kingdom).
· Section Editor (2016 – contd.);Optik – International Journal for Light and Electron Optics (ISSN: 0030-4026; Published by Elsevier, Amsterdam, The Netherlands).
· Editorial Board Member; International Journal of Humanitarian Technology (ISSN: 2056-6549; Published by Inderscience Publishers, Switzerland).
· Editorial Board Member;Asian Journal of Physics (ISSN: 0971-3093; Published by Anita Publications, India).
· Reviewer for Books/Journals:
o Books: Wiley & Sons; CRC Press.
o Journals: Journal of Lightwave Technology; IEEE Photonics Technology Letters; IEEE Transections on Nanotechnology; Optics Communications; Optical Engineering; Optik – International Journal for Light and Electron Optics; IET Communications; Journal of Nanophotonics; Optics and Laser Technology; Laser Physics; International Journal of Microwave and Optical Technology; Progress in Electromagnetics Research; International Journal of Optics; Journal of Electromagnetic Waves and Applications; International Journal of Applied Electromagnetics and Mechanics; Advances in Optical Technologies; Optical and Quantum Electronics; Journal of Modern Optics; Journal of Nanomaterials; Nuclear Science and Techniques; Journal of Optoelectronics and Advanced Materials; Waves in Random and Complex Media; Optical Fiber Technology; Physics Letters A; Journal of Applied Remote Sensing; Applied Optics; Mathematical Methods in the Applied Sciences; International Journal of Infrared, Millimeter & Terahertz Waves; Journal of the European Optical Society – Rapid Publications; Optics Letters; Zeitschrift für Naturforschung A; IET Circuits, Devices & Systems; Engineering Research Express; Physics of Plasmas; AIP Advances; Physica E: Low-Dimensional Systems and Nanostructures; Results in Physics; Superlattices and Microstructures; Physica Scripta; Nanoscale; IET Nanobiotechnology; Measurements; Journal of Physics D – Applied Physics; Materials Today Communications; Biosensors and Bioelectronics; Advanced Optical Materials; Materials Letters; Applied Nanoscience; Nanotechnology.
· Fellow; The Institution of Engineering & Technology (IET, UK;#1100412473)
· Fellow;The Society of Photo-Optical & Instrumentation Engineers (SPIE, USA; #777880)
· Senior Member;The Institute of Electrical & Electronics Engineers (IEEE, USA; #41564251)
· Lifetime Senior Member;Optica (formerly OSA, USA; #359416)