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2018

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Articles 961 - 990 of 1644

Full-Text Articles in Electrical and Computer Engineering

Versatile Soliton Emission From A Ws2 Mode-Locked Fiber Laser, Bo Guo, Shi Li, Ya-Xian Fan, Pengfei Wang Jan 2018

Versatile Soliton Emission From A Ws2 Mode-Locked Fiber Laser, Bo Guo, Shi Li, Ya-Xian Fan, Pengfei Wang

Articles

Recently, few-layer tungsten disulfide (WS2), as a shining 2D material, has been discovered to possess both the saturable absorption ability and large nonlinear refractive index. Here, we demonstrate versatile soliton pulses in a passively mode-locked fiber laser with a WS2-deposited microfiber. The few-layer WS2 is prepared by the liquid-phase exfoliation method and transferred onto a microfiber by the optical deposition method. Study found, the WS2-deposited microfiber can operate simultaneously as a mode-locker and a high-nonlinear device. In experiment, by further inserting the WS2 device into the fiber laser, besides the dual-wavelength soliton, noise-like soliton pulse, conventional soliton and its harmonic …


Fabrication And Characterization Of A Magnetized Metal-Encapsulated Fbg Sensor For Structural Health Monitoring, Sagar Jinachandran, Huijun Li, Jiangtao Xi, B. Gangadhara Prusty, Yuliya Semenova, Gerald Farrell, Ginu Rajan Jan 2018

Fabrication And Characterization Of A Magnetized Metal-Encapsulated Fbg Sensor For Structural Health Monitoring, Sagar Jinachandran, Huijun Li, Jiangtao Xi, B. Gangadhara Prusty, Yuliya Semenova, Gerald Farrell, Ginu Rajan

Articles

A novel means of metal packaging of a fiber Bragg grating (FBG) sensor using stainless steel and tin, together with high temperature resistant samarium cobalt (SmCo) magnet is proposed in this paper. The inclusion of high temperaturecapable SmCo magnets enable the metal packaging of the FBG sensor with magnetic capabilities. This packaged sensor can be placed in direct contact with the substrate structures such as iron pipelines and other ferromagnetic components without any adhesives, making them easily detachable and reusable. This is a significant improvement compared with other commercial fiber optic sensors which are, surface attached using epoxies or welded …


Optimal Operation Of Integrated Microgrids, Abdullah Albaker Jan 2018

Optimal Operation Of Integrated Microgrids, Abdullah Albaker

Electronic Theses and Dissertations

Microgrids' deployments are increasing and projected to increase even more in future due to the significant advantages that are provided by this technology for end-use customers. However, microgrids can be connected to each other to create integrated microgrids system, which can further promote the anticipated and desired benefits. An integrated operation of microgrids can potentially improve the local power system reliability and resilience, increase the individual microgrids' economic benefits, and promote further utilization of renewable energy resources. Integrating microgrids, to achieve a microgrid network or cluster, is expected be an essential application towards smarter power grids and a key operational …


Study Of Optical Ofdm System For Wireless Lan Applications, Salih Mohamed S. Kenshil Jan 2018

Study Of Optical Ofdm System For Wireless Lan Applications, Salih Mohamed S. Kenshil

Electronic Theses and Dissertations

The advantages of optical fiber make it possible to extend the data rate transmission and propagation distance. Orthogonal frequency division multiplexing (OFDM) as a multicarrier technique (MC) is used in hybrid optical-wireless system designs because it has the best spectral efficiency to radio frequency (RF) interference and lower multipath distortion. In this dissertation, a study and evaluation of optical OFDM based wireless local area network (W-LAN) systems are presented. The baseband of the OFDM signal is fully transmitted and up-converted to a radio frequency signal. Also, to reduce system costs, simple base stations (BSs) are interconnected to a central office …


Design Of Power Switched-Capacitor Converters And Their Performance Analysis In A Soft-Charging Operation, Ayoob Alateeq Jan 2018

Design Of Power Switched-Capacitor Converters And Their Performance Analysis In A Soft-Charging Operation, Ayoob Alateeq

Electronic Theses and Dissertations

Switched-capacitor (SC) converters have gained more interest due to their high power density and appropriateness for small circuit integration. Building a SC DC-to-DC converter with only capacitors and switches is the main reason to seek a higher power density achievement. However, the SC converters suffer dominant losses related to their capacitors and switches. These losses can be determined and optimized by calculating the converter's output impedance in its two asymptotic limits.

We proposed a high voltage gain and a very low output impedance power switched-capacitor converter (PSC) with a lower number of components compared to other step-up switched-capacitor topologies. The …


Robust Distributed Stabilization Of Interconnected Multiagent Systems, Vahid Rezaei Jan 2018

Robust Distributed Stabilization Of Interconnected Multiagent Systems, Vahid Rezaei

Electronic Theses and Dissertations

Many large-scale systems can be modeled as groups of individual dynamics, e.g., multi-vehicle systems, as well as interconnected multiagent systems, power systems and biological networks as a few examples. Due to the high-dimension and complexity in configuration of these infrastructures, only a few internal variables of each agent might be measurable and the exact knowledge of the model might be unavailable for the control design purpose. The collective objectives may range from consensus to decoupling, stabilization, reference tracking, and global performance guarantees. Depending on the objectives, the designer may choose agent-level low-dimension or multiagent system-level high-dimension approaches to develop distributed …


Optimal Planning Of Microgrid-Integrated Battery Energy Storage, Ibrahim S. Alsaidan Jan 2018

Optimal Planning Of Microgrid-Integrated Battery Energy Storage, Ibrahim S. Alsaidan

Electronic Theses and Dissertations

Battery energy storage (BES) is a core component in reliable, resilient, and cost-effective operation of microgrids. When appropriately sized, BES can provide the microgrid with both economic and technical benefits. Besides the BES size, it is found that there are mainly three planning parameters that impact the BES performance, including the BES integration configuration, technology, and depth of discharge.

In this dissertation, the impact of each one of these parameters on the microgrid-integrated BES planning problem is investigated. Three microgrid-integrated BES planning models are developed to individually find the optimal values for the aforementioned parameters. These three microgrid-integrated BES planning …


Control And Optimization Of Power In Llc Converter Using Phase Control, Nagasri Kollipara Jan 2018

Control And Optimization Of Power In Llc Converter Using Phase Control, Nagasri Kollipara

Browse all Theses and Dissertations

LLC resonant converters are popular among resonant topologies due to their high efficiency and ability to achieve ZVS and ZCS for wide input range. LLC resonant converters are controlled by frequency modulation (FM), which makes converter difficult to optimize the system in terms of achieving efficient power conversion. FM technique also generate wide range of harmonics which leads to a wide sweep in operating frequency, which can run into regulatory EMI test limits and cause electromagnetic compatibility issues. The performance of LLC topology extends to their poor efficiency at lighter loads, due to constant high magnetization current. In order to …


Modeling And Simulation Of Inductive-Based Wireless Power Transmission Systems, Mohammad Haerinia Jan 2018

Modeling And Simulation Of Inductive-Based Wireless Power Transmission Systems, Mohammad Haerinia

Electrical Engineering Student Publications

This chapter studies an inductive-based wireless power transfer system for low-power applications at short distances. The transferring power system has been modeled, simulated and analyzed via finite element method. A wireless power transfer system includes important parts such as coil, core and driver. In this chapter, the important parts of an inductive power transfer system have been analyzed. Receiving and transmitting printed spiral coils are designed in an optimized procedure. The experimental results were in a good agreement with the simulation results. Moreover, based on the performed modulation and simulation the use of the pot core as the receiving core …


Examination Of Gain Scheduling And Fuzzy Controllers With Hybrid Reachability, Aaron W. Fifarek Jan 2018

Examination Of Gain Scheduling And Fuzzy Controllers With Hybrid Reachability, Aaron W. Fifarek

Browse all Theses and Dissertations

Modern aircraft with nonlinear flight envelopes predominately utilize gain scheduled controllers to provide stability of flight. Using gain scheduled control techniques, nonlinear envelopes can be linearized into collections of linear systems that operate under various system dynamics. Linear controllers approximate the nonlinear response over setpoints of operating conditions which allow traditional linear theory to be applied to maintain stability. Techniques to prove linear stability are well understood and realized in control systems, but when controllers are switched, interpolation methods must be used. Interpolation is necessary as gain scheduled systems do not have foundational switching paradigms as part of their realization …


A Lightweight Classification Algorithm For Human Activity Recognition In Outdoor Spaces, Graham Mccalmont, Huiru Zheng, Haiying Wang, S. I. Mcclean, Matteo Zallio, Damon Berry Jan 2018

A Lightweight Classification Algorithm For Human Activity Recognition In Outdoor Spaces, Graham Mccalmont, Huiru Zheng, Haiying Wang, S. I. Mcclean, Matteo Zallio, Damon Berry

Conference Papers

The aim of this paper is to discuss the development of a lightweight classification algorithm for human activity recognition in a defined setting. Current techniques to analyse data such as machine learning are often very resource intensive meaning they can only be implemented on machines or devices that have large amounts of storage or processing power. The lightweight algorithm uses Euclidean distance to measure the difference between two points and predict the class of new records.

The results of the algorithm are largely positive achieving accuracy of 100% when classifying records taken from the same sensor position and accuracy of …


A Review Of Multimode Interference In Tapered Optical Fibers And Related Applications, Pengfei Wang, Haiyan Zhao, Xianfan Wang, Gerald Farrell, Gilberto Brambilla Jan 2018

A Review Of Multimode Interference In Tapered Optical Fibers And Related Applications, Pengfei Wang, Haiyan Zhao, Xianfan Wang, Gerald Farrell, Gilberto Brambilla

Conference papers

In recent years, tapered optical fibers (TOFs) have attracted increasing interest and developed into a range of devices used in many practical applications ranging from optical communication, sensing to optical manipulation and high-Q resonators. Compared with conventional optical fibers, TOFs possess a range of unique features, such as large evanescent field, strong optical confinement, mechanical flexibility and compactness. In this review, we critically summarize the multimode interference in TOFs and some of its applications with a focus on our research project undertaken at the Optoelectronics Research Centre of the University of Southampton in the United Kingdom.


A Comparative Study Of Chisel For Fpga Design, Paul Lennon, Richard Gahan Jan 2018

A Comparative Study Of Chisel For Fpga Design, Paul Lennon, Richard Gahan

Conference Papers

This paper presents the results of a comparative study conducted into designing with the Chisel hardware construction language against the Verilog hardware description language across a range of standard-library and bespoke FPGA design components including an N-bit FIFO, a round-robin arbiter and a complex, scalable arbiter. Comparison metrics such as maximum operating frequency, silicon area, design flow run-time, source-code density and maintainability, simulation run-time and speed of coding are employed to evaluate the merits of designing with Chisel. Each component is implemented with a deep low-level hardware understanding with an aim to evaluate the merits of designing with Chisel from …


Design And Analysis Of Class Ef2 Inverter For Driving Transmitting Printed Spiral Coil, Mohammad Haerinia, Ebrahim S. Afjei Jan 2018

Design And Analysis Of Class Ef2 Inverter For Driving Transmitting Printed Spiral Coil, Mohammad Haerinia, Ebrahim S. Afjei

Electrical Engineering Student Publications

This paper studies a high frequency inverter for low power applications at a short distance. Class 𝐸𝐹2 inverter is selected and designed as a transmitting driver. A printed spiral coil is designed as a transmitting coil and is connected to the high frequency inverter. Experimental results are obtained to compare with simulation results. The experiment and simulation are in good agreement and the circuit design is verified. Operating frequency is 2.75 MHz. Maximum flux density is generated by transmitting coil is measured 149uT.


Microdisk Resonator With Negative Thermal Optical Coefficient Polymer For Refractive Index Sensing With Thermal Stability, Tao Ma, Jinhui Yuan, Feng Li, Lei Sun, Zhe Kang, Binbin Yan, Qiang Wu, Xinzhu Sang, Heng Liu, Fang Wang, Bo Wu, Chongxiu Yu, Gerald Farrell Jan 2018

Microdisk Resonator With Negative Thermal Optical Coefficient Polymer For Refractive Index Sensing With Thermal Stability, Tao Ma, Jinhui Yuan, Feng Li, Lei Sun, Zhe Kang, Binbin Yan, Qiang Wu, Xinzhu Sang, Heng Liu, Fang Wang, Bo Wu, Chongxiu Yu, Gerald Farrell

Articles

In this paper, we propose a microdisk resonator with negative thermal optical coefficient (TOC) polymer for refractive index (RI) sensing with thermal stability. The transmission characteristics and sensing performances by using quasi-TE01 and quasi-TM01 modes are simulated by a three-dimensional finite element method. The influences of the TOC, RI, and thickness of the polymer on the sensing performances are also investigated. The simulation results show that the RI sensitivity Sn and temperature sensitivity ST with different polymers are in the ranges of 25.1-26 nm/RIU and 67.3-75.2 pm/K for the quasi-TE01 mode, and 94.5-110.6 nm/RIU and 1.2-51.3 pm/K for the quasi-TM01 …


Virtual Reality Based Serious Games For Stna Training, Ryan Thomas Kall Jan 2018

Virtual Reality Based Serious Games For Stna Training, Ryan Thomas Kall

Undergraduate Research Posters 2018

In this project, exploratory steps have been taken towards the development of a set of serious games for state tested nursing assistants (STNAs) education and training, which promises to make the training more engaging and effective. Tasks include getting familiar with developing 3D scenes with Unity, human activity recognition with Microsoft Kinect, creating holograms with Microsoft HoloLens, and help implement a gaze-based mechanism for performance assessment in patient transfer skills.


A Quantitative Analysis Of The Performance Of Computing Architectures Used In Neural Simulations, Daniel Chang, Kyle Daruwalla, Nathaniel Olivero, Allison Pluger, Sunil Rao, Mario Simoni Jan 2018

A Quantitative Analysis Of The Performance Of Computing Architectures Used In Neural Simulations, Daniel Chang, Kyle Daruwalla, Nathaniel Olivero, Allison Pluger, Sunil Rao, Mario Simoni

Faculty Publications - Electrical and Computer Engineering

No abstract provided.


Dynamic Choke Sensing For Timing Error Resilience In Ntc Systems, Aatreyi Bal, Shamik Saha, Sanghamitra Roy, Koushik Chakraborty Jan 2018

Dynamic Choke Sensing For Timing Error Resilience In Ntc Systems, Aatreyi Bal, Shamik Saha, Sanghamitra Roy, Koushik Chakraborty

Electrical and Computer Engineering Faculty Publications

Process variation (PV) is a conspicuous predicament for submicrometer VLSI circuits. In this paper, we illustrate "choke points" as a vital consequence of PV in the near-threshold computing domain. Choke points are PV affected sensitized logic gates with increased delay deviation. They dominate the choice of critical paths postfabrication. To mitigate the timing errors induced thereby, we propose dynamic choke sensing (DCS). This technique senses the timing error causing opcode sequences, and uses the knowledge to prevent similar sequences from causing errors in the future. We propose two variants of our scheme. Our techniques provide ~55% improvement in performance and …


Creating A Consistent Oceanic Multi-Decadal Intercalibrated Tmi-Gmi Constellation Data Record, Ruiyao Chen Jan 2018

Creating A Consistent Oceanic Multi-Decadal Intercalibrated Tmi-Gmi Constellation Data Record, Ruiyao Chen

Electronic Theses and Dissertations

The Tropical Rainfall Measuring Mission (TRMM), launched in late November 1997 into a low earth orbit, produced the longest microwave radiometric data time series of 17-plus years from the TRMM Microwave Imager (TMI). The Global Precipitation Measuring (GPM) mission is the follow-on to TRMM, designed to provide data continuity and advance precipitation measurement capabilities. The GPM Microwave Imager (GMI) performs as a brightness temperature (Tb) calibration standard for the intersatellite radiometric calibration (XCAL) for the other constellation members; and before GPM was launched, TMI was the XCAL standard. This dissertation aims at creating a consistent oceanic multi-decadal Tb data record …


Generation And Characterization Of Isolated Attosecond Pulse In The Soft X-Ray Regime, Jie Li Jan 2018

Generation And Characterization Of Isolated Attosecond Pulse In The Soft X-Ray Regime, Jie Li

Electronic Theses and Dissertations

The observation of any atomic and molecular dynamics requires a probe that has a timescale comparable to the dynamics itself. Ever since the invention of laser, the temporal duration of the laser pulse has been incrementally reduced from several nanoseconds to just attoseconds. Picosecond and femtosecond laser pulses have been widely used to study molecular rotation and vibration. In 2001, the first single isolated attosecond pulse (1 attosecond = 10^-18 seconds.) was demonstrated. Since this breakthrough, "attoscience" has become a hot topic in ultrafast physics. Attosecond pulses typically have span between EUV to X-ray photon energies and sub-femtosecond pulse duration. …


Effect Of Nonclassical Optical Turbulence On A Propagating Laser Beam, Melissa Beason Jan 2018

Effect Of Nonclassical Optical Turbulence On A Propagating Laser Beam, Melissa Beason

Electronic Theses and Dissertations

Theory developed for the propagation of a laser beam through optical turbulence generally assumes that the turbulence is both homogeneous and isotropic and that the associated spectrum follows the classical Kolmogorov spectral power law of κ-11/3. If the atmosphere deviates from these assumptions, beam statistics such as mean intensity, correlation, and scintillation index could vary significantly from mathematical predictions. This work considers the effect of nonclassical turbulence on a propagated beam. Namely, anisotropy of the turbulence and a power law that deviates from κ-11/3. A mathematical model is developed for the scintillation index of a Gaussian beam propagated through nonclassical …


Energy Slices: Benchmarking With Time Slicing, Katarina Grolinger, Hany F. Elyamany, Wilson Higashino, Miriam Am Capretz, Luke Seewald Jan 2018

Energy Slices: Benchmarking With Time Slicing, Katarina Grolinger, Hany F. Elyamany, Wilson Higashino, Miriam Am Capretz, Luke Seewald

Electrical and Computer Engineering Publications

Benchmarking makes it possible to identify low-performing buildings, establishes a baseline for measuring performance improvements, enables setting of energy conservation targets, and encourages energy savings by creating a competitive environment. Statistical approaches evaluate building energy efficiency by comparing measured energy consumption to other similar buildings typically using annual measurements. However, it is important to consider different time periods in benchmarking because of differences in their consumption patterns. For example, an office can be efficient during the night, but inefficient during operating hours due to occupants’ wasteful behavior. Moreover, benchmarking studies often use a single regression model for different building categories. …


Compound Glass Microsphere Resonator Devices, Jibo Yu, Elfed Lewis, Gerald Farrell, Pengfei Wang Jan 2018

Compound Glass Microsphere Resonator Devices, Jibo Yu, Elfed Lewis, Gerald Farrell, Pengfei Wang

Articles

In recent years, compound glass microsphere resonator devices have attracted increasing interest and have been widely used in sensing, microsphere lasers, and nonlinear optics. Compared with traditional silica resonators, compound glass microsphere resonators have many significant and attractive properties, such as high-Q factor, an ability to achieve high rare earth ion, wide infrared transmittance, and low phonon energy. This review provides a summary and a critical assessment of the fabrication and the optical characterization of compound glasses and the related fabrication and applications of compound glass microsphere resonators.


Energising Dairy Decisions, John Upton, Philip Shine, Michael Breen, Michael D. Murphy Jan 2018

Energising Dairy Decisions, John Upton, Philip Shine, Michael Breen, Michael D. Murphy

Publications

A new tool developed by Teagasc researchers easily and quickly allows dairy farmers to see their energy usage and evaluate how renewable sources could decrease energy costs.


Human Activity Tracking And Recognition Using Kinect Sensor, Roanna Lun Jan 2018

Human Activity Tracking And Recognition Using Kinect Sensor, Roanna Lun

ETD Archive

The objective of this dissertation research is to use Kinect sensor, a motion sensing input device, to develop an integrated software system that can be used for tracking non-compliant activity postures of consented health-care workers for assisting the workers' compliance to best practices, allowing individualized gestures for privacy-aware user registration, movement recognition using rule-based algorithm, real-time feedback, and exercises data collection. The research work also includes developing a graphical user interface and data visualization program for illustrating statistical information for administrator, as well as utilizing cloud based database system used for data resource.


School Logo Cleveland State University Logo Title Evolutionary Optimization For Safe Navigation Of An Autonomous Robot In Cluttered Dynamic Unknown Environments, Arash Roshanineshat Jan 2018

School Logo Cleveland State University Logo Title Evolutionary Optimization For Safe Navigation Of An Autonomous Robot In Cluttered Dynamic Unknown Environments, Arash Roshanineshat

ETD Archive

We present a path planning approach based on probabilistic methods for a robot to navigate in a cluttered, dynamic, unknown environment. There are dynamic obstacles moving around and static obstacles located in the map. The robot does not have any prior information about them but should be able to navigate through the map beginning from a known starting point and safely ending at a known target point. The only information the robot has is the location of the starting point and the target point and it uses sensory information to collect information about its surroundings. Our method is compared to …


A Transformative Process Control Solution, Simone Castanho Nobrega De Almedia Soares Jan 2018

A Transformative Process Control Solution, Simone Castanho Nobrega De Almedia Soares

ETD Archive

Knowing that a technology invented almost hundred years ago (PID controller) is still dominating industrial process control, a historical review was done to understand how the control field evolved. Model dependency and high level of mathematics appear as the main reasons that prevent other technologies from penetrating the engineering practice. A relatively novel methodology introduced by J. Han in 1998 called Active Disturbance Rejection Control (ADRC) came with characteristics that matches process control needs and restrictions on model dependency. This study will present a transformative solution for process control based on that. The control algorithm is designed and discretized for …


A Framework For Energy Monitoring Of Machining Workshops Based On Iot, Xingzheng Chen, Congbo Li, Ying Tang, Li Li, Qinge Xiao Jan 2018

A Framework For Energy Monitoring Of Machining Workshops Based On Iot, Xingzheng Chen, Congbo Li, Ying Tang, Li Li, Qinge Xiao

Henry M. Rowan College of Engineering Departmental Research

Machining workshop is a widely distributed manufacturing system that consumes massive energy in low efficiency. Due to the complicated and dynamic energy flow of the machining workshop, machinery manufacturers still lack an effective method to monitor and manage the energy efficiency. Hence, this paper proposes an energy efficiency monitoring system for machining workshop with the support of the newly emerging Internet of Things (IoT) technology. With the application of the proposed system, potential opportunities for energy efficiency improvement can be identified. Machinery manufacturers can easily reduce energy consumption and energy cost by managing the machining process.


Uneven-Layered Coding Metamaterial Tile For Ultrawideband Rcs Reduction And Diffuse Scattering, Jianxun Su, Huan He, Zengrui Li, Yaoqing Lamar Yang, Hongcheng Yin, Junhong Wang Jan 2018

Uneven-Layered Coding Metamaterial Tile For Ultrawideband Rcs Reduction And Diffuse Scattering, Jianxun Su, Huan He, Zengrui Li, Yaoqing Lamar Yang, Hongcheng Yin, Junhong Wang

Department of Electrical and Computer Engineering: Faculty Publications

In this paper, a novel uneven-layered coding metamaterial tile is proposed for ultra-wideband radar cross section (RCS) reduction and diffuse scattering. The metamaterial tile is composed of two kinds of square ring unit cells with different layer thickness. The reflection phase difference of 180° (±37°) between two unit cells covers an ultra-wide frequency range. Due to the phase cancellation between two unit cells, the metamaterial tile has the scattering pattern of four strong lobes deviating from normal direction. The metamaterial tile and its 90-degree rotation can be encoded as the ‘0’ and ‘1’ elements to cover an object, and diffuse …


Ultraviolet Laser Photolysis Of Hydrocarbons For Nondiamond Carbon Suppression In Chemical Vapor Deposition Of Diamond Films, Li-Sha Fan, Loic Constantin, Da-Wei Li, Lei Liu, Kamran Keramatnejad, Clio Azina, Xi Huang, Hossein Rabiee Golgir, Yao Lu, Zahra Ahmadi, Fei Wang, Jeffrey E. Shield, Bai Cui, Jean-Francois Silvain, Yong-Feng Lu Jan 2018

Ultraviolet Laser Photolysis Of Hydrocarbons For Nondiamond Carbon Suppression In Chemical Vapor Deposition Of Diamond Films, Li-Sha Fan, Loic Constantin, Da-Wei Li, Lei Liu, Kamran Keramatnejad, Clio Azina, Xi Huang, Hossein Rabiee Golgir, Yao Lu, Zahra Ahmadi, Fei Wang, Jeffrey E. Shield, Bai Cui, Jean-Francois Silvain, Yong-Feng Lu

Department of Electrical and Computer Engineering: Faculty Publications

In this work, we demonstrate that ultraviolet (UV) laser photolysis of hydrocarbon species alters the flame chemistry such that it promotes the diamond growth rate and film quality. Optical emission spectroscopy and laser-induced fluorescence demonstrate that direct UV laser irradiation of a diamond-forming combustion flame produces a large amount of reactive species that play critical roles in diamond growth, thereby leading to enhanced diamond growth. The diamond growth rate is more than doubled, and diamond quality is improved by 4.2%. Investigation of the diamond nucleation process suggests that the diamond nucleation time is significantly shortened and nondiamond carbon accumulation is …