Events

Nov 26 - Dec 3, 2023

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  Binary Diffractive Optical Elements for structured light applications

  Redha Al Ibrahim, Postdoctoral Research Fellow, Electrical and Computer Engineering

  Nov 30, 14:00 - 15:00

  B2 L5 R5209

  Light can be controlled through different degrees of freedom. An optical field is described through frequency, amplitude, phase, polarization, and wave-front structure. Many applications have been explored using these degrees of freedom, and some have great importance in our daily life.

Oct 1 - Oct 15, 2023

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  Low-Coherence Surface-Emitting Lasers for Optical Wireless Communication and Low-Speckle Illumination

  Omar Alkhazragi, Ph.D. Student, Electrical and Computer Engineering

  Oct 8, 10:00 - 11:30

  B2 L5 R5220

  Highly coherent light, although beneficial in specific applications, suffers from the formation of speckles, resulting in poor imaging, lighting, and projection/display quality. Moreover, the long coherence length limits the resolution in interference based sensing. The aim of this dissertation is to design low-coherence surface-emitting lasers to push simultaneous illumination and optical wireless communication (OWC) toward reliable implementation with higher speeds.

May 7 - May 21, 2023

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  KAUST-Fudan Joint Workshop on Intelligent Communication, Device and System Technologies

  Boon Ooi, Professor, Electrical and Computer Engineering

  May 14, 09:00 - 16:00

  B18 L4 Fellowship Hall

  Intelligent Communication photonics

  This joint workshop between KAUST and Fudan University covers a variety of topics related to optical communication and devices for visible light communication. Theoretical modeling, device engine/materials investigation and sub-system development will be discussed. These research are essential to eventually realize the goals of connecting all the unconnected, SMART systems and optical internet-of-things. The workshop will be running in hybrid mode, and presenters will be from both KAUST and Fudan University.

Feb 5 - Feb 12, 2023

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  Photonics Design and Remote Sensing

  Prof. Hugo Enrique Hernandez Figueroa

  Feb 7, 14:00 - Feb 9, 16:00

  B18 L4 Fellowship Hall

  photonics remote sensing

  Abstract This tutorial series will include: Seminar 1 (Monday, 2PM) – Electromagnetic Numerical Modeling A general view of electromagnetic numerical modeling. Finite Element Method (FEM) vs Finite Difference Method. FEM formulations for solving Maxwell equations: time-domain and frequencydomain. Scattering, resonant structures and guiding modeling. Description of NEO-PZ: LEMAC’s electromagnetic simulator package. Challenging electromagnetic problems: very large electrical spatial domains demanding very high localized accuracy. Deterministic and heuristic optimization techniques and artificial

Oct 23 - Nov 6, 2022

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  Toward scalable and high performance on-chip light source for integrated silicon photonics

  Chen Shang, Postoctoral Researcher Fellow, University of California Santa Barbara

  Oct 30, 12:00 - 13:00

  B9 L2 R2322

  Integrated Photonics technology

  Monolithic integration of quantum dot (QD) gain materials onto Si photonic platforms via direct epitaxial growth is considered as the ultimate solution for on-chip light sources.

Aug 28 - Sep 4, 2022

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  Compound Semiconductor Weekend

  Integrated Photonics Laboratory; Smart, Advanced Memory devices and Applications Laboratory; Photonics Laboratory; Advanced Semiconductor Laboratory

  Sep 3, 09:00 - Sep 5, 17:00

  B3 L5 R5209

  The Compound Semiconductor Weekend will focus on some of the most important research areas on the beautiful KAUST campus by the Red Sea. It features 18 invited and contributed oral talks and a poster competition. Semiconductor technology is a major foundation of the third and fourth Industrial Revolutions as well as the modern society. While silicon remains as the widest-employed semiconductor, compound semiconductors have emerged from lab research to becoming the second most widely used within a short period of time. This is because compound semiconductors could possess multiple superior key properties simultaneously. They include high speed, high power, and efficient light emission and absorption, as well as that they can be produced in large scale at low cost and are highly robust. As a result, they have become cornerstones of many crucial technologies including lighting, display, communication, space exploration, and electric vehicles. While semiconductor researchers are plowing deeper for those technologies, compound semiconductors attract increasing attention for future computing, memory, and quantum information science as the pursuit of Moore’s Law has slowed down dramatically when the size of silicon transistors is approaching the physical limit of a few atoms.

Jul 3 - Jul 10, 2022

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  Integrated Photonic Devices for Sensing and Telecom Applications

  Prof. Hugo E. Hernandez Figueroa, University of Campinas (UNICAMP)

  Jul 6, 10:00 - 11:30

  B3 L5 R5209

  Integrated Photonics technology

  This talk will be focused on Integrated Photonics technology, which demands strong and robust confinement of light in order to attain the maximum possible integration of photonics devices on a single chip. Keeping this in mind, three applications based on LEMAC’s recent developments will be presented in this talk.

Mar 13 - Mar 27, 2022

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  Underwater optical communication and sensing technology in silent ocean

  Yujian Guo, Ph.D. Student, Electrical and Computer Engineering

  Mar 20, 13:00 - 15:00

  KAUST

  underwater optical communications Underwater wireless optical communication

  This dissertation aims to investigate and address noisy ocean issues and build large-scale underwater sensor networks by optical communication and sensing technology. The dissertation proposes using UWOC and FC&S technology to replace the conventional acoustic communication technology and reduce the noise in the ocean. UWOC helps achieve high-speed wireless communications between sensors, vehicles, and even humans for UIoT. The significant challenges of developing UWOC systems are the complex underwater environment's attenuation, scattering, and turbulence effects. This dissertation studied the turbulence effects on the UWOC system’s performance and addressed the pointing-acquisition-and-tracking issues.

Nov 7 - Nov 14, 2021

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  Characterization of non-conventional methods for alignment relaxation in underwater wireless optical communication systems

  Mohammed Sait, Ph.D. Student, Electrical and Computer Engineering

  Nov 11, 15:00 - 16:00

  B3 L3 R5220

  The paradigm of Internet of Underwater Things (IoUT) is expected to enable various practical applications such as environmental monitoring, underwater exploration, and disaster prevention. Supporting the concept of IoUT requires robust underwater wireless communication infrastructure. Optical wireless communication has the superiority of wide bandwidth, low latency and high data capacity over its counterparts namely, acoustic and radio frequency.
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  Deep-Ultraviolet Optoelectronics Based on GaN Quantum Disks and Bio-Inspired Nanostructures

  Ram Chandra Subedi, Ph.D. Student, Electrical and Computer Engineering

  Nov 10, 18:00 - 19:00

  B3 L5 R5209

  Optoelectronics in the deep-ultraviolet (DUV) regime is still a growing research field that requires significant effort to understand the material properties and optimize the device structures to realize highly efficient DUV devices. Of all the wide bandgap materials, AlGaN is perhaps the most studied semiconductor to replace the environmentally hazardous mercury lamps; however, the external quantum efficiency (EQE) of AlGaN based DUV devices is insufficient to replace the existing old-fashioned mercury UV lamps.
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  Hybrid inorganic heterostructures and methods of fabricating p-type semiconductors for optoelectronic devices

  Jian Wei Liang, Ph.D. Student, Electrical and Computer Engineering

  Nov 8, 14:00 - 16:00

  KAUST

  Semiconductor devices based on wide-bandgap materials exhibit a higher breakdown voltage, temperature tolerance, and device stability, and lower energy loss than devices based on low-bandgap materials. Several limitations challenge the use of III-nitrides and transition metal oxides as wide-bandgap materials. This thesis proposes novel methods to surmount these issues.

Mar 7 - Mar 14, 2021

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  Generation of Orbital Angular Momentum (OAM) Modes with Spiral Phase Plate Integrated Laser Source

  Edgars Stegenburgs, Ph.D. Student, Electrical and Computer Engineering

  Mar 10, 12:00 - 14:00

  KAUST

  The objective of this work is to develop a near-infrared laser device capable of emitting orbital angular momentum (OAM) light. The prototyped device must be suitable for compact, energy-saving optical communication applications. Integrated OAM lasers would revolutionize high capacity data transmission over any telecommunication network environment as OAM light can be guided and transmitted through kilometers of optical fibers as well as propagated in free space and underwater.

Sep 13 - Sep 20, 2020

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  High-Speed GaN-Based Distributed-Feedback Lasers and Optoelectronics

  Jorge A. Holguin-Lerma, Ph.D. Student, Electrical and Computer Engineering

  Sep 17, 09:30 - 11:00

  KAUST

  Gallium nitride (GaN) is a semiconductor material highly regarded for visible light generation since it provides the most efficient platform for compact violet, blue, and green light emitters, and in turn, high-quality and ubiquitous white lighting. Despite this fact, the potential of the GaN platform has not been fully exploited. This potential must enable the precise control in the various properties of light, realizing functions beyond the conventional. Simultaneously, the field of the telecommunications is looking for candidate technologies fit for wireless transmission in the next generations of communication. Visible light communication (VLC) may play a significant role in the future of the last mile of the network by providing both a fast internet connection and a high-quality illumination.

Mar 29 - Apr 5, 2020

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  Fabrication and Characterization of GaN-Based Superluminescent Diode for Solid-State Lighting and Visible Light Communication

  Abdullah A. Alatawi, Ph.D. Student, Electrical and Computer Engineering

  Apr 2, 16:00 - 18:00

  KAUST

  Fabrication and Characterization solid-state lighting Visible light communications

  This dissertation is devoted to the fabrication and electrical and optical characterization of a new class of III-nitride light-emitter known as superluminescent diode (SLD). SLD works in an amplified spontaneous emission (ASE) regime, and it combines several advantages from both LD and LED, such as droop-free, speckle-free, low-spatial coherence, broader emission, high-optical power, and directional beam. Here, SLDs were fabricated by a focused ion beam by tilting the front facet of the waveguide to suppress the lasing mode. They showed a high-power of 474 mW on c-plane GaN-substrate with a large spectral bandwidth of 6.5 nm at an optical power of 105 mW. To generate SLD-based white light, a YAG-phosphor-plate was integrated, and a CRI of 85.1 and CCT of 3392 K were measured. For the VLC link, SLD showed record high-data rates of 1.45 Gbps and 3.4 Gbps by OOK and DMT modulation schemes, respectively. Additionally, a widely single- and dual-wavelength tunability were designed using SLD-based external cavity (SLD-EC) configuration for a tunable blue laser source.
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  Ultraviolet band based underwater wireless optical communication

  Xiaobin Sun, Ph.D. Student, Electrical and Computer Engineering

  Apr 1, 10:00 - 12:00

  KAUST

  Optical communications optical wireless communicaitons communication networks photonics

  Underwater wireless optical communication (UWOC) has attracted increasing interest for data transfer in various underwater activities, due to its order-of-magnitude higher bandwidth compared to conventional acoustic and radio-frequency (RF) technologies. Our studies pave the way for eventual applications of UWOC by relieving the strict requirements on PAT using UV-based NLOS. Such modality is much sought-after for implementing robust, secure, and high-speed UWOC links in harsh oceanic environments. This work was first started with the investigation of proper NLOS configurations. Path loss (PL) was chosen as a figure-of-merit for link performance. The effects of NLOS geometries, water turbidity, and transmission wavelength are evaluated by measuring the corresponding PL. The experimental results suggest that NLOS UWOC links are favorable for smaller azimuth angles, stronger water turbidity, and shorter transmission wavelength, as exemplified by the use of 375-nm wavelength. With the understanding of favorable NLOS UWOC configurations, we established a NLOS link consisting of an ultraviolet (UV) laser as the transmitter for enhanced light scattering and high sensitivity photomultiplier tube (PMT) as the receiver. A high data rate of 85 Mbit/s using on-off keying (OOK) in a 30-cm emulated highly turbid harbor water is demonstrated. Besides the underwater communication links, UV-based NLOS is also appealing to be the signal carrier for direct communication across wavy water-air interface. The trial results indicate link stability, which alleviates the issues brought about by the misalignment and mobility in harsh environments, paving the way towards real applications.

Feb 9 - Feb 23, 2020

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  Distributed Multi-parameter Sensing Using a Multimode Fiber

  Islam Ashry, Senior Research Scientist, Electrical and Computer Engineering

  Feb 16, 12:30 - 13:00

  B9 L2 H1 R2322

  Graduate Seminar Part 2. Fiber-optic distributed acoustic sensor (DAS) and distributed temperature sensor (DTS) are considered important for many applications. It is challenging to design a hybrid DAS-DTS system using the same optical fiber because the operation principles of the two sensors are different. In this talk, we summarize the concept of using the widespread standard multimode fiber (MMF) for simultaneous distributed acoustic and temperature sensing. In particular, we operate the MMF in a quasi-single-mode (QSM) state to simultaneously fulfill the functional requirements of the DAS and DTS. This technique is significant for many industrial applications because it efficiently tackles a long-standing issue in practical implementation.
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  Epitaxial growth of group-III nitride semiconductors on amorphous fused silica glass and its heterogeneous integration for optoelectronic devices

  Jung-Wook Min, Research Scientist, Photonics Laboratory

  Feb 16, 12:00 - 12:30

  B9 L2 H1 R2322

  Graduate Seminar Part 1. In this talk, catalyst- and mask-free GaN nanowires ensemble were grown by plasma-assisted molecular beam epitaxy (PA-MBE) under nitrogen-rich condition. Prior to optoelectronic device realization, we conducted fundamental studies including diffusion-induced growth mechanisms on various substrates. On bare fused silica substrate, without any buffer layer, hundreds-of-nanometer scale grains of GaN nanowires were examined by SEM and interfaces were investigated by TEM. Despite the poly-crystalline properties of the coalescent columnar GaN layer, each grain showed the preferential orientation along the c-axis growth direction. To provide conductivity and transparency on amorphous fused silica as a thermally durable substrate, transparent conductive oxide (TCO) layers were deposited by RF magnetron sputtering method on a fused silica glass substrate. Next, for the heterogeneous integration toward solar cell application, we introduced n-GaN nanowires as an electron transport layer (ETL) for methylammonium lead iodide (MAPbI3) perovskite solar cells (PSCs). n-GaN nanowires showed high electron mobility and UV blocking characteristics with MAPbI3. Moreover, finite-difference time-domain (FDTD) simulation confirmed that the roughened interfaces of GaN nanowire arrays are helpful for photon recycling. These achievements can open a new pathway for the heterogeneous integration of group-III nitride and perovskite semiconductors and substrate-independent epitaxy.

Nov 24 - Dec 1, 2019

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  KAUST-Asia Wide Bandgap Semiconductor Workshop

  Nov 29, 08:00 - Nov 30, 18:00

  KAUST Main Library L3 R3118

  The fast-developing wide bandgap semiconductor technologies have created hundred-billion-dollar market globally and are crucial for numerous critical areas in Saudi Arabia including water security, lighting, power supply, communication, and nuclear management. This workshop features distinguished speakers from more than 15 leading research institutions and a poster competition. It will serve as a bridge to strengthen the connections of KAUST with Asia for collaboration opportunities in research, development, and commercialization of wide bandgap semiconductor technologies. View the agenda here.

Nov 10 - Nov 17, 2019

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  Deep-Ultraviolet Optoelectronic Devices Enabled by the Hybrid Integration of Next-Generation Semiconductors and Emerging Device Platforms

  Nasir Alfaraj, Ph.D., Electrical and Computer Engineering

  Nov 11, 18:00 - 20:00

  B3 L5 R5209

  photonics ultraviolet wavelengths optoelectronics

  In this dissertation, the design and fabrication of deep-ultraviolet photodetectors, based on gallium oxide and its alloys, through the heterogeneous integration with metallic and other inorganic materials is investigated. The crystallographic properties of grown oxide films formed directly and indirectly on silicon, magnesium oxide, and sapphire are examined, and the challenges that hinder the realization of efficient and reliable deep-ultraviolet photodetectors are elaborated on. I provide an overview of aluminum nitride, gallium oxide, sapphire, and silicon substrates as platforms for deep-ultraviolet optoelectronic devices, in which I elaborate on the challenges associated with using sapphire as a platform for efficient deep-ultraviolet devices and detail advancements in device growth and fabrication on silicon and magnesium oxide substrates.

Oct 13 - Oct 27, 2019

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  Hybrid integration of materials for ultraviolet detection

  Tien Khee Ng, Principal Research Scientist, Photonics Laboratory

  Oct 20, 12:00 - 13:00

  B9 L2 H1 R2322

  semiconductors electronics optoelectronics AlInGaN-based lasers LED silicon-based photodetectors solving technological challenges ultraviolet detection Optical communications

  Semiconductors are pervasive in consumer electronics and optoelectronics, and the related optical devices are deemed disruptive that Nobel Prize in Physics in 2014 was awarded to the inventors of blue light-emitting diodes (LEDs), which “has enabled bright and energy-saving white light sources”. While AlInGaN-based lasers and LEDs, and silicon-based photodetectors are currently matured, unconventional usage based on the materials has demonstrated their further potential, including solar-hydrogen generation, indoor-horticulture, and high-speed communication.

Sep 15 - Sep 22, 2019

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  Visible Light Communications in the UK: Recent Progress and Future Outlook

  Dr. Paul Anthony Haigh,Lecturer in Communications, Intelligent Sensing and Communications Group,Newcastle University

  Sep 17, 13:00 - 14:00

  B2 L5 R5220

  Visible light communications

  Abstract Visible light communications (VLC) is a hot topic in internet access networks, developing rapidly over the last decade. It has become one of the main candidate technologies to complement existing radio infrastructure in 5G and beyond technologies due to its inherent advantages such as high bandwidth and room-to-room security. In this talk, I will discuss several of the key developments that have occurred within the context of the UK research community, with particular focus on polymer photoactive components based on research that has occurred through my time at University College

Sep 8 - Sep 15, 2019

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  Study of III-nitride Nanowire Growth and Devices on Unconventional Substrates

  Aditya Prabaswara, Ph.D., Electrical and Computer Engineering

  Sep 12, 09:30 - 11:00

  B3 L5 R5209

  semiconductors III-nitride nanowires optoelectronics

  This thesis aims to investigate the microscopic characteristics of the nanowires and expand on the possibility of using transparent amorphous substrate for III-nitride nanowire devices. In this work, we performed material growth, characterization, and device fabrication of III-nitride nanowires grown using molecular beam epitaxy on unconventional substrates including silicon substrates and fused silica substrates. We also investigated the effect of various nucleation layers on the morphology and quality of the nanowires.

Sep 1 - Sep 15, 2019

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  Laser lighting and its application in visible light communications

  Boon Ooi, Professor, Electrical and Computer Engineering

  Sep 8, 12:00 - 13:00

  B9 L2 R2322

  laser-lighting Visible light communications Underwater communication high-speed transmitters high-speed receivers

  This talk provides an overview of the latest laser-based lighting and Gbit/s VLC and underwater communications. Recent progress of visible wavelength high-speed transmitters and receivers will also be discussed.

Jul 28 - Aug 4, 2019

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  Study of ultraviolet AlGaN nanowires light-emitting diodes

  Davide Priante, Ph.D., Electrical and Computer Engineering

  Jul 30, 16:00 - 17:00

  B3 L5 R5209

  photonics optoelectronics nanofabrication

  Ultraviolet (UV) group III-Nitride-based light emitters have been used in various applications such as water purification, medicine, lighting and chemical detection. Despite attractive properties such as bandgap tunability in the whole UV range (UV-C to UV-A), high chemical stability and relative low cost, the low quantum efficiency hamper the full utilization. This thesis aims to show alternative solutions to such problems by employing nanowires (NWs) structures, and target the eventual application of reliable and high power NWs-based light-emitting devices, enabling large-scale production using the established silicon foundry processes. Here, we present the improvement of injection current and optical power of AlGaN NWs LEDs by involving a metal bilayer thin film with a dual purpose: eliminate the potential barrier for carrier transport, and inhibit the formation of silicide.

Mar 24 - Apr 7, 2019

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  Visible light communication

  Guangyu Liu, Research Scientist, Photonics Laboratory

  Mar 31, 12:00 - 13:00

  B9 H1

  vlc communications

  The wireless communication technology has been evolved from 1G to 5G networks. The next 6G era will bring about higher demands for bandwidth and speed. Visible light communication (VLC) shows great potential in providing high speed and secure communication link by utilizing the unregulated visible light spectrum to carry the data. In this seminar, the overview of VLC will be presented first. The devices and components developed for VLC network will then be reviewed and discussed in details. I will also briefly talk about the application of underwater communication application by using visible light at the end of the seminar.