Research Of Electro-Optical Effect In Metal Halide Perovskites By Fabry-Perot Interometer Method, 2019 Washington University in St. Louis
Research Of Electro-Optical Effect In Metal Halide Perovskites By Fabry-Perot Interometer Method, Hanxiang Yin
Engineering and Applied Science Theses & Dissertations
Perovskites have been investigated a lot by present and reported with outstanding optoelectronic properties. However, so far there is no publications about another important property, the electro-optical (EO) effect which is related to important applications in photolithography. This thesis is mainly mean to calculate the EO constants of one kind of organic perovskite material, CH3NH3PbI3, which has been reported to have good capability of forming film by spin-coating, through the way of putting the film of CH3NH3PbI3 between two layers of metal mirrors to build a Fabry-Perot interferometer and characterizing ...
Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, 2019 Purdue University
Urban Underground Infrastructure Monitoring Iot: The Path Loss Analysis, Abdul Salam, Syed Shah
The extra quantities of wastewater entering the pipes can cause backups that result in sanitary sewer overflows. Urban underground infrastructure monitoring is important for controlling the flow of extraneous water into the pipelines. By combining the wireless underground communications and sensor solutions, the urban underground IoT applications such as real time wastewater and storm water overflow monitoring can be developed. In this paper, the path loss analysis of wireless underground communications in urban underground IoT for wastewater monitoring has been presented. It has been shown that the communication range of up to 4 kilometers can be achieved from an underground ...
An Underground Radio Wave Propagation Prediction Model For Digital Agriculture, 2019 Purdue University
An Underground Radio Wave Propagation Prediction Model For Digital Agriculture, Abdul Salam
Underground sensing and propagation of Signals in the Soil (SitS) medium is an electromagnetic issue. The path loss prediction with higher accuracy is an open research subject in digital agriculture monitoring applications for sensing and communications. The statistical data are predominantly derived from site-specific empirical measurements, which is considered an impediment to universal application. Nevertheless, in the existing literature, statistical approaches have been applied to the SitS channel modeling, where impulse response analysis and the Friis open space transmission formula are employed as the channel modeling tool in different soil types under varying soil moisture conditions at diverse communication distances ...
Ultrashort Cross-Correlation In The Middle Infrared: A Novel Approach To Standoff Detection, 2019 University of Nebraska-Lincoln
Ultrashort Cross-Correlation In The Middle Infrared: A Novel Approach To Standoff Detection, William Conner Thomas
Theses, Dissertations, and Student Research from Electrical & Computer Engineering
Lasers are a common tool in standoff detection because of their small divergence, large amount of power, and multiple wavelengths available for optical interaction. Optical signatures of targets can be composed of but are not limited to absorption, fluorescence, backscatter, polarization manipulation, and plasma spectra. This work was an investigation of a new signature phenomenon: Dispersion of middle infrared ultrashort laser pulses through gas and vapor phase molecules. Vibrational and rovibrational absorption lines of molecular species affect the spectral phase and spectral amplitude of ultrashort light pulses leading an inititally gaussian temporal profile to become distorted. This dissertation is an ...
Inverse Design Of Three-Dimensional Nanoantennas For Metasurface Applications, 2019 United States Military Academy
Inverse Design Of Three-Dimensional Nanoantennas For Metasurface Applications, Danny Zhu, Eric B. Whiting, Sawyer D. Campbell, Pingjuan L. Werner, Douglas H. Werner
West Point Research Papers
Recent advances in manufacturing techniques have been made to match the demand for high performance optical devices. To this end, tremendous research activity has been focused on optical metasurfaces as they offer a unique potential to achieve disruptive designs when paired with innovative fabrication techniques and inverse design tools. However, most metasurface designs have revolved around canonical geometries. While these elements are relatively easy to fabricate, they represent only a small portion of the design space, and rarely offer peak performance in transmission, phase range or field of view. In this work, a Lazy Ant Colony Optimization (LACO) technique is ...
Development Of A Set Of Pre-Class Videos For Electromagnetic Theory, 2019 Anderson University - Indiana
Development Of A Set Of Pre-Class Videos For Electromagnetic Theory, Benjamin Mcpheron, Josiah D. Kunz
ASEE IL-IN Section Conference
One important aspect of experiential learning is allowing students time to reflect on new concepts before the application of the material. Most commonly, this is attempted by assigning readings from a textbook, but research suggests that few students complete these readings. This discouraging fact has prompted the use of other resources, such as videos, to supplement pre-class readings in order to introduce new material. Previous work has been completed by this author to produce pre-class videos for use in an introductory circuits course. This paper extends that work to the development of pre-class videos for a senior level electrical engineering ...
Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two ﬂuorocarbon Gases Chf3 And Cf4, 2019 Singh Center for Nanotechnology
Reactive Ion Etching Selectivity Of Si/Sio2: Comparing Of Two ﬂuorocarbon Gases Chf3 And Cf4, Meiyue Zhang, Pat Watson
Protocols and Reports
Two reactive ion etching (RIE) processes were studied to show the relative etch selectivity between SiO2 and Si using two ﬂuorocarbon gases, CF4 and CHF3. Results show that CHF3 gives better selectivity (16:1) over CF4 (1.2 :1). On the other hand, the etch rate of SiO2 of CF4 is approximately 52.8 nm/min, faster than CHF3 (32.4 nm/min).
A Theoretical Model Of Underground Dipole Antennas For Communications In Internet Of Underground Things, Abdul Salam, Mehmet C. Vuran, Xin Dong, Christos Argyropoulos, Suat Irmak
The realization of Internet of Underground Things (IOUT) relies on the establishment of reliable communication links, where the antenna becomes a major design component due to the significant impacts of soil. In this paper, a theoretical model is developed to capture the impacts of change of soil moisture on the return loss, resonant frequency, and bandwidth of a buried dipole antenna. Experiments are conducted in silty clay loam, sandy, and silt loam soil, to characterize the effects of soil, in an indoor testbed and field testbeds. It is shown that at subsurface burial depths (0.1-0.4m), change in soil ...
Investigating The Role Of Coil Designs And Anatomical Variations In Cerebellar Tms, 2019 Iowa State University
Investigating The Role Of Coil Designs And Anatomical Variations In Cerebellar Tms, Xiaojing Zhong, Priyam Rastogi, Yifei Wang, Erik G. Lee, David C. Jiles
Electrical and Computer Engineering Publications
Transcranial magnetic stimulation (TMS) is a non-invasive neuromodulation technique that is used for treating various neurological disorders such as major depressive disorder. TMS has been gaining popularity in the field of neurostimulation of the cerebellum, since the cerebellum is a complex structure connected with almost the entire central nervous system and TMS has promise for non-invasively probing cerebellar function. Recent studies have discovered that the cerebellum plays an important role not only in motor planning and behavior but also in the cognitive domain. However, few studies have explored how different coil designs and anatomical variations affect the effectiveness of cerebellar ...
Optically Transparent Antennas And Filters For Smart City Communication, 2019 Virginia Commonwealth University
Optically Transparent Antennas And Filters For Smart City Communication, Ryan B. Green
Theses and Dissertations
Incremental usage of mobile devices demand a new generation of wireless networks (5G) to provide faster data rates, more reliable coverage, monitor city infrastructure usage, and increase network capacity. The frequencies proposed for the upcoming 5G network would result in shorter broadcast distances and network dead zones, countered by incorporating transparent antennas into glass high rises. Transparent antennas possess, however a major challenge: low gain. This lower gain can be countered by means of employing antennas in an antenna array, boosting the gain and even giving the array the ability to beam form for the upcoming 5G network. The 5G ...
Optical Micro-Seismometer Based On Evanescent Field Perturbation Of Whispering Gallery Modes, 2018 Southern Methodist University
Optical Micro-Seismometer Based On Evanescent Field Perturbation Of Whispering Gallery Modes, Jaime Da Silva
Mechanical Engineering Research Theses and Dissertations
This thesis proposes a light-weight, compact, and accurate optical micro-seismometer that could be used in many applications, such as planetary exploration. The sensor proposed here is based on the principle of whispering gallery optical mode (WGM) resonance shifts of a dielectric micro-resonator due to disturbances of its evanescent field. The micro-seismometer could be used in place of the traditional bulky seismometers. The design of a waveguide-resonator and mechanical structure to disturb the evanescent field are presented. A proof-of-concept a seismometer model that uses a 5µm ring resonator is numerically tested with actual seismic data. The results show that a WGM-based ...
Growth And Behaviors Of Inn/Gan Multiple Quantum Wells By Plasma-Assisted Molecular Beam Epitaxy, 2018 University of Arkansas, Fayetteville
Growth And Behaviors Of Inn/Gan Multiple Quantum Wells By Plasma-Assisted Molecular Beam Epitaxy, Chen Li
Theses and Dissertations
Fully realizing the potential of InGaN semiconductors requires high quality materials with arbitrary In-content. To this date the growth of In-rich InGaN films is still challenging since it suffers from the low growth temperatures and many detrimental alloying problems. InN/GaN multiple quantum wells (MQWs) and super lattices (SLs) are expected to be promising alternatives to random InGaN alloys since in principle they can achieve the equivalent band gap of InGaN random alloys with arbitrarily high In-content and at the same time bypass many growth difficulties.
This dissertation focuses on studying the growth mechanisms, structural properties and energy structures of ...
Growth And Characterization Of Silicon-Germanium-Tin Semiconductors For Future Nanophotonics Devices, 2018 University of Arkansas, Fayetteville
Growth And Characterization Of Silicon-Germanium-Tin Semiconductors For Future Nanophotonics Devices, Bader Saad Alharthi
Theses and Dissertations
The bright future of silicon (Si) photonics has attracted research interest worldwide. The ultimate goal of this growing field is to develop a group IV based Si foundries that integrate Si-photonics with the current complementary metal–oxide–semiconductor (CMOS) on a single chip for mid-infrared optoelectronics and high speed devices. Even though group IV was used in light detection, such as photoconductors, it is still cannot compete with III-V semiconductors for light generation. This is because most of the group IV elements, such as Si and germanium (Ge), are indirect bandgap materials. Nevertheless, Ge and Si attracted industry attention because ...
Effective Magnetic And Electric Response Of Composite Materials, 2018 Louisiana Tech University
Effective Magnetic And Electric Response Of Composite Materials, Mona Hassan Alsaleh
Metamaterials (MMs) are nanocomposite materials consisting of metal-dielectric resonators much smaller in size than the wavelength of the incident light. Common examples of metamaterials are based on split ring resonators (SRRs), parallel wires or strips and fishnet structures. These types of materials are designed and fabricated in order to provide unique optical responses to the incident electromagnetic radiation that are not available in naturally existing materials. The MMs can exhibit unusual properties such as strong magnetism at terahertz (THz) and optical frequencies. Additionally, negative index materials (NIMs) can provide negative index of refraction which can be used in many applications ...
Electromagnetic Wave-Matter Interactions In Complex Opto-Electronic Materials And Devices, 2018 Louisiana Tech University
Electromagnetic Wave-Matter Interactions In Complex Opto-Electronic Materials And Devices, Raj Kumar Vinnakota
This dissertation explores the fundamentals of light-matter interaction towards applications in the field of Opto-electronic and plasmonic devices. In its core, this dissertation attempts and succeeds in the the modeling of light-matter interactions, which is of high importance for better understanding the rich physics underlying the dynamics of electromagnetic field interactions with charged particles. Here, we have developed a self-consistent multi-physics model of electromagnetism, semiconductor physics and thermal effects which can be readily applied to the field of plasmotronics and Selective Laser Melting (SLM). Plasmotronics; a sub-field of photonics has experienced a renaissance in recent years by providing a large ...
Transcribing Braille Code: Learning Equations Across Platforms, 2018 Purdue University
Transcribing Braille Code: Learning Equations Across Platforms, Deegan Atha, Courtney Balogh
Purdue Journal of Service-Learning and International Engagement
Deegan Atha, a graduating senior in electrical engineering and a future engineer, is interested in human-centered design and developing technology that helps students engage and be successful in STEM.
Courtney Balogh, a junior in mechanical engineering, is interested in human-centered design and the importance it plays in product development. Deegan and Courtney are members of the Purdue EPICS project, Learning Equations Across Platforms (LEAP). They partnered with the Indiana School for the Blind and Visually Impaired (ISBVI) to develop a braille transcription device and web application that converts braille to print in real time.
Genetic Algorithm Design Of Photonic Crystals For Energy-Efficient Ultrafast Laser Transmitters, 2018 University of New Mexico
Genetic Algorithm Design Of Photonic Crystals For Energy-Efficient Ultrafast Laser Transmitters, Troy A. Hutchins-Delgado
Shared Knowledge Conference
Photonic crystals allow light to be controlled and manipulated such that novel photonic devices can be created. We are interested in using photonic crystals to increase the energy efficiency of our semiconductor whistle-geometry ring lasers. A photonic crystal will enable us to reduce the ring size, while maintaining confinement, thereby reducing its operating power. Photonic crystals can also exhibit slow light that will increase the interaction with the material. This will increase the gain, and therefore, lower the threshold for lasing to occur. Designing a photonic crystal for a particular application can be a challenge due to its number of ...
Study Of Physical Layer Security And Teaching Methods In Wireless Communications, 2018 NC A&T State Unversity
Study Of Physical Layer Security And Teaching Methods In Wireless Communications, Zhijian Xie, Christopher Horne
KSU Proceedings on Cybersecurity Education, Research and Practice
In most wireless channels, the signals propagate in all directions. For the communication between Alice and Bob, an Eavesdropper can receive the signals from both Alice and Bob as far as the Eavesdropper is in the range determined by the transmitting power. Through phased array antenna with beam tracking circuits or cooperative iteration, the signals are confined near the straight line connecting the positions of Alice and Bob, so it will largely reduce the valid placement of an Eavesdropper. Sometimes, this reduction can be prohibitive for Eavesdropper to wiretap the channel since the reduced space can be readily protected. Two ...
A Narrow-Wall Complementary-Split-Ring Slotted Waveguide Antenna For High-Power-Microwave Applications, 2018 University of New Mexico
A Narrow-Wall Complementary-Split-Ring Slotted Waveguide Antenna For High-Power-Microwave Applications, Xuyuan Pan
Electrical and Computer Engineering ETDs
A narrow-band, rugged, complementary-split-ring (CSR) slotted waveguide antenna (SWA) with significant size reduction is presented. The antenna is to be vertically front mounted on a land vehicle, with a horizontally polarized fan-beam radiation pattern. The radiation characteristics of a CSR slot in the narrow-wall of a rectangular waveguide are studied for the first time in this work. Both simulation and experimental results show that the complementary-split-ring slot radiates a linearly polarized wave with a total efficiency and gain close to those of conventional longitudinal slots, while the proposed CSR slots have a maximal outer diameter of 0.23λ0, much ...
Tailoring The Asymmetric Magnetoimpedance Response In Exchange-Biased Ni - Fe Multilayers, 2018 University of Nebraska - Lincoln