High-Resolution Dynamic Strain Sensor Using A Polarization-Maintaining Fiber Bragg Grating,
2019
University of Alabama in Huntsville
High-Resolution Dynamic Strain Sensor Using A Polarization-Maintaining Fiber Bragg Grating, Dipen Barot, Gang Wang, Lingze Duan
PRC-Affiliated Research
Dynamic strain sensing based on fiber Bragg gratings (FBG) has found a wide range of applications in structural health monitoring and industrial process control. Conventional approaches to enhance strain resolution upon the standard configuration have shown challenges in scaling up due to much increased system complexity. In this report, we demonstrate a new scheme based on an FBG sensor fabricated in a polarization-maintaining fiber. By using balanced detection to suppress laser intensity noise and enhance strain signal, we have demonstrated an improvement of 28 dB in signal level, 18 dB in signal-to-noise ratio, and 20× in strain resolution when compared …
Experimental Study And Modeling Of The Gm-I Dependence Of Long-Channel Mosfets,
2019
California Polytechnic State University, San Luis Obispo
Experimental Study And Modeling Of The Gm-I Dependence Of Long-Channel Mosfets, Michael Fong Cheng
Master's Theses
This thesis describes an experimental study and modeling of the current-transconductance dependence of the ALD1106, ALD1107, and CD4007 arrays. The study tests the hypothesis that the I-gm dependence of these 7.8 µm to 10 µm MOSFETs conforms to the Advanced Compact Model (ACM). Results from performed measurements, however, do not support this expectation. Despite the relatively large length, both ALD1106 and ALD1107 show sufficiently pronounced ‘short-channel’ effects to render the ACM inadequate. As a byproduct of this effort, we confirmed the modified ACM equation. With an m factor of approximately 0.6, it captures the I-gm dependence with sub-28% maximum error …
Electromagnon Excitation In Cupric Oxide Measured By Fabry-Pérot Enhanced Terahertz Mueller Matrix Ellipsometry,
2019
University of Nebraska - Lincoln
Electromagnon Excitation In Cupric Oxide Measured By Fabry-Pérot Enhanced Terahertz Mueller Matrix Ellipsometry, Sean Knight, Dharmalingam Prabhakaran, Christian Binek, Mathias Schubert
Christian Binek Publications
Here we present the use of Fabry-Pérot enhanced terahertz (THz) Mueller matrix ellipsometry to measure an electromagnon excitation in monoclinic cupric oxide (CuO). As a magnetically induced ferroelectric multiferroic, CuO exhibits coupling between electric and magnetic order. This gives rise to special quasiparticle excitations at THz frequencies called electromagnons. In order to measure the electromagnons in CuO, we exploit single-crystal CuO as a THz Fabry-Pérot cavity to resonantly enhance the excitation’s signature. This enhancement technique enables the complex index of refraction to be extracted. We observe a peak in the absorption coefficient near 0.705 THz and 215 K, which corresponds …
Fabrication And Characterization Of Planar-Structure Perovskite Solar Cells,
2019
University of Kentucky
Fabrication And Characterization Of Planar-Structure Perovskite Solar Cells, Guoduan Liu
Theses and Dissertations--Electrical and Computer Engineering
Currently organic-inorganic hybrid perovskite solar cells (PSCs) is one kind of promising photovoltaic technology due to low production cost, easy fabrication method and high power conversion efficiency.
Charge transport layers are found to be critical for device performance and stability. A traditional electron transport layer (ETL), such as TiO2 (Titanium dioxide), is not very efficient for charge extraction at the interface. Compared with TiO2, SnO2 (Tin (IV) Oxide) possesses several advantages such as higher mobility and better energy level alignment. In addition, PSCs with planar structure can be processed at lower temperature compared to PSCs with …
Aptamer Functionalized Zinc Oxide Field Effect Transistors For Odor Detection,
2019
West Virginia University
Aptamer Functionalized Zinc Oxide Field Effect Transistors For Odor Detection, Michael D. Aldridge
Graduate Theses, Dissertations, and Problem Reports (ETD)
Odor detection and identification are complex processes, and tasks that currently only animals do well. There is a pressing need for an electronic nose, or eNose, with good sensitivity, selectivity, and speed that mimics that ability. Food quality control operations, environmental sensing, occupational safety, and the defense sectors all require systems that can rapidly and reliably detect trace levels of volatile organic compounds. The goal of this work is to create a biologically inspired device which can accurately detect and identify odors at concentrations consistent with the most sensitive biological systems.
In order to mimic a natural olfactory system, we …
Straintronic Nanomagnetic Devices For Non-Boolean Computing,
2019
Virginia Commonwealth University
Straintronic Nanomagnetic Devices For Non-Boolean Computing, Md Ahsanul Abeed
Theses and Dissertations
Nanomagnetic devices have been projected as an alternative to transistor-based switching devices due to their non-volatility and potentially superior energy-efficiency. The energy efficiency is enhanced by the use of straintronics which involves the application of a voltage to a piezoelectric layer to generate a strain which is ultimately transferred to an elastically coupled magnetostrictive nanomaget, causing magnetization rotation. The low energy dissipation and non-volatility characteristics make straintronic nanomagnets very attractive for both Boolean and non-Boolean computing applications. There was relatively little research on straintronic switching in devices built with real nanomagnets that invariably have defects and imperfections, or their adaptation …
Optical And Electrical Analysis Of Zno/Znte Micropillar Solar Cells,
2019
Bucknell University
Optical And Electrical Analysis Of Zno/Znte Micropillar Solar Cells, Sadia Binte Sohid
Master’s Theses
The prime focus of the energy-research community in recent times has been replacing fossil fuels with renewable energy. Therefore, photovoltaic research areas are rapidly expanding in this era. The purpose of this work is to compare three different structural ZnO/ZnTe solar cell types (planar, axial micropillar and radial micropillar). The best optical and electrical performance has been obtained by the radial junction (core-shell) ZnO/ZnTe micropillar solar cell due to its pillar structure and radial junction. The unique advantage of the radial junction micropillar is that the angle of the incident light and the carrier collection is orthogonal. Therefore, the pillar …
Fabrication And Characterization Of Nanofiber Nylon-6-Mwcnt As An Electrochemical Sensor For Sodium Ions Concentration Detection In Sweat,
2019
The University of Akron
Fabrication And Characterization Of Nanofiber Nylon-6-Mwcnt As An Electrochemical Sensor For Sodium Ions Concentration Detection In Sweat, Kelsey Mills
Williams Honors College, Honors Research Projects
Fabrication and characterization nylon-6-MWCNT nanofiber as an electrochemical sensor to detect sodium ion concentrations specifically in sweat. Using contact angle to determine surface morphology and chronoamperometry testing to identify ideal sensor conditions, tests optimized parameters like weight percent of nylon or other polymers, carbon nanotube (CNT) isomer, and solution concentration to determine reproducibility of functional sensors. Utilizing the electric qualities of carbon nanotubes partnered with the sodium ion selectivity of calixarene treatment and polymers unique properties like flexibility and scalability create open an arena for optimizing sodium ion sensors for further development for functional prototypes. Morphology tests showed that the …
Limitations Of Zt As A Figure Of Merit For Nanostructured Thermoelectric Materials,
2019
Purdue University
Limitations Of Zt As A Figure Of Merit For Nanostructured Thermoelectric Materials, Xufeng Wang, Mark Lundstrom
Department of Electrical and Computer Engineering Faculty Publications
Thermoelectric properties of nanocomposites are numerically studied as a function of average grain size or nanoparticle density by simulating the measurements as they would be done experimentally. In accordance with previous theoretical and experimental results, we find that the Seebeck coefficient, power factor and figure of merit, zT, can be increased by nanostructuring when energy barriers exist around the grain boundaries or embedded nanoparticles. When we simulate the performance of a thermoelectric cooler with the same material, however, we find that the maximum temperature difference is much less than expected from the given zT. This occurs because the …
S.A.V.E. M.E.,
2019
The University of Akron
S.A.V.E. M.E., Taylor Davis, Kelly Nicole O'Neill, Adrianna M. Dunlap, Parsa Esshaghi Bayat
Williams Honors College, Honors Research Projects
S.A.V.E. M.E. stands for Submerged Automated Vehicular Elevation Minor Extraction or alternatively a Home Swimming Pool Rescue Device. The objective of this project is to design and prototype a system that will make unattended swimming pools through detecting a victim’s presence, deploying a means to save the victim, and alerting others nearby of the situation. This system encompasses sensors and devices within the pool and an alarm system outside of the pool. Upon detection of a sufficiently sized object entering the pool when the system is armed, a device will maneuver to the victim and deploy a flotation device that …
Resonant Acoustic Wave Assisted Spin-Transfer-Torque Switching Of Nanomagnets,
2019
Virginia Commonwealth University
Resonant Acoustic Wave Assisted Spin-Transfer-Torque Switching Of Nanomagnets, Austin R. Roe
Theses and Dissertations
We studied the possibility of achieving an order of magnitude reduction in the energy dissipation needed to write bits in perpendicular magnetic tunnel junctions (p-MTJs) by simulating the magnetization dynamics under a combination of resonant surface acoustic waves (r-SAW) and spin-transfer-torque (STT). The magnetization dynamics were simulated using the Landau-Lifshitz-Gilbert equation under macrospin assumption with the inclusion of thermal noise. We studied such r-SAW assisted STT switching of nanomagnets for both in-plane elliptical and circular perpendicular magnetic anisotropy (PMA) nanomagnets and show that while thermal noise affects switching probability in in-plane nanomagnets, the PMA nanomagnets are relatively robust to the …
Energy Efficient Spintronic Device For Neuromorphic Computation,
2019
Virginia Commonwealth University
Energy Efficient Spintronic Device For Neuromorphic Computation, Md Ali Azam
Theses and Dissertations
Future computing will require significant development in new computing device paradigms. This is motivated by CMOS devices reaching their technological limits, the need for non-Von Neumann architectures as well as the energy constraints of wearable technologies and embedded processors. The first device proposal, an energy-efficient voltage-controlled domain wall device for implementing an artificial neuron and synapse is analyzed using micromagnetic modeling. By controlling the domain wall motion utilizing spin transfer or spin orbit torques in association with voltage generated strain control of perpendicular magnetic anisotropy in the presence of Dzyaloshinskii-Moriya interaction (DMI), different positions of the domain wall are realized …
Fabrication And Simulation Of Nanomagnetic Devices For Information Processing,
2019
Virginia Commonwealth University
Fabrication And Simulation Of Nanomagnetic Devices For Information Processing, Justine L. Drobitch
Theses and Dissertations
Nanomagnetic devices are highly energy efficient and non-volatile. Because of these two attributes, they are potential replacements to many currently used information processing technologies, and they have already been implemented in many different applications. This dissertation covers a study of nanomagnetic devices and their applications in various technologies for information processing – from simulating and analyzing the mechanisms behind the operation of the devices, to experimental investigations encompassing magnetic film growth for device components to nanomagnetic device fabrication and measurement of their performance.
Theoretical sections of this dissertation include simulation-based modeling of perpendicular magnetic anisotropy magnetic tunnel junctions (p-MTJ) and …
Engineering Plasmonic Nanostructures For Light Management And Sensing,
2019
West Virginia University
Engineering Plasmonic Nanostructures For Light Management And Sensing, Sujan Phani Kumar Kasani
Graduate Theses, Dissertations, and Problem Reports (ETD)
The two major global problems are to provide health safety and to meet energy demands for ever growing population on a large scale. The study of light interaction with nanostructures has shown a promising solution in improving the fields of bio-sensor and solar energy devices which addresses above mentioned two major global problems. Nanostructures have tunable physicochemical properties such as light absorption, electrical and thermal properties unlike bulk materials, which gives an advantage in applications like bio-sensing and energy harvesting devices. The development of nanofabrication techniques along with the discovery of Surface Enhanced Raman Scattering (SERS) and Plasmon Enhanced Fluorescence …
Furnace System Improvements,
2018
California Polytechnic State University, San Luis Obispo
Furnace System Improvements, Kenji K. Anzai, Ethan Fedor, Patrick Zailaa
Mechanical Engineering
This Final Design Review (FDR) documents the work done by the group to manufacture the system to deliver improvements to the furnace in the Cal Poly microfabrication laboratory (better known as the cleanroom). The document describes the material covered in the Scope of Work (SOW), including background research, customer needfinding, and the problem statement, material associated with concept development and selection for Preliminary Design Review (PDR), material detailing the design and manufacturing plan of the system for Critical Design Review (CDR), and new material detailing the manufacture of the system for FDR.
Research done for the SOW resulted in a …
Exfoliation, Synthesis, And Characterization Of Nanoscale Te,
2018
University of Arkansas, Fayetteville
Exfoliation, Synthesis, And Characterization Of Nanoscale Te, Takayuki Hironaka
Graduate Theses and Dissertations
Since the experimental discovery of graphene, two dimensional materials have enjoyed more attention and emphasis in academic research than nanowires, but the latter are an important area of study for creating 1D materials, or single atom chains, the next generation materials for advancing electronic devices. Atomically thin layers can be generated from 2D materials with weak bonds in one direction, and by applying this concept to one dimensional weakly bonded materials, we hypothesize that single atom chains with atomic-scale diameters may be produced. Tellurium (Te) and selenium (Se) have lattices consisting of spiral chains oriented along the c-axis, and each …
Gesn Thin Film Epitaxy And Quantum Wells For Optoelectronic Devices,
2018
University of Arkansas, Fayetteville
Gesn Thin Film Epitaxy And Quantum Wells For Optoelectronic Devices, Perry Christian Grant
Graduate Theses and Dissertations
Group IV photonics is an effort to generate viable infrared optoelectronic devices using group IV materials. Si-based optoelectronics have received monumental research since Si is the heart of the electronics industry propelling our data driven world. Silicon however, is an indirect material whose optical characteristics are poor compared to other III-IV semiconductors that make up the optoelectronics industry. There have been major efforts to integrate III-V materials onto Si substrates. Great progress on the integration of these III-V materials has occurred but incompatibility with CMOS processing has presented great difficulty in this process becoming a viable and cost-effective solution. Germanium …
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
Graduate 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 InN/GaN …
Fabrication And Characterization Of Electrochemical Glucose Sensors,
2018
University of Arkansas, Fayetteville
Fabrication And Characterization Of Electrochemical Glucose Sensors, Mohammed Marie
Graduate Theses and Dissertations
Electrochemical sensors based on the nanostructure of the semiconductor materials are of tremendous interest to be utilized for glucose monitoring. The sensors, based on the nanostructure of the semiconductor materials, are the third generations of the glucose sensors that are fast, sensitive, and cost-effect for glucose monitoring.
Glucose sensors based on pure zinc oxide nanorods (NRs) grown on different substrates, such ITO, FTO, and Si/SiO2/Au, were investigated in this research. Silicon nanowire (NW)- based glucose sensors were also studied. First, an enzyme-based glucose sensor was fabricated out of glass/ITO/ZnO NRs/BSA/GOx/nafion membrane. The sensor was tested amperometrically at different glucose concentrations. …
Exploration Of Radiation Damage Mechanism In Mems Devices.,
2018
University of Louisville
Exploration Of Radiation Damage Mechanism In Mems Devices., Pranoy Deb Shuvra
Electronic Theses and Dissertations
We explored UV, X-ray and proton radiation damage mechanisms in MEMS resonators. T-shaped MEMS resonators of different dimensions were used to investigate the effect of radiation. Radiation damage is observed in the form of resistance and resonance frequency shift of the device. The resistance change indicates a change in free carrier concentration and mobility, while the resonance frequency change indicates a change in mass and/or elastic constant. For 255nm UV radiation, we observed a persistent photoconductivity that lasts for about 60 hours after radiation is turned off. The resonance frequency also decreases 40-90 ppm during irradiation and slowly recovers at …
