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Full-Text Articles in Engineering

Flux-Quanta Injection For Nonreciprocal Current Control In A Two-Dimensional Noncentrosymmetric Superconducting Structure, Serafim Teknowijoyo, Sara Chahid, Armen Gulian Jul 2023

Flux-Quanta Injection For Nonreciprocal Current Control In A Two-Dimensional Noncentrosymmetric Superconducting Structure, Serafim Teknowijoyo, Sara Chahid, Armen Gulian

Mathematics, Physics, and Computer Science Faculty Articles and Research

We designed and experimentally demonstrated a four-terminal superconducting device, a “quadristor,” that can function as a nonlatching (reversible) superconducting switch from the diode regime to the resistive state by application of a control current much smaller than the main transport current. The device uses a vortex-based superconducting-diode mechanism that is switched back and forth via the injection of flux quanta through auxiliary current leads. Our finding opens a new research area in the field of superconducting electronics.


Analysis Of Degradation Of Sb2se3 Thin Film Solar Cells Deploying A Time-Dependent Approach Linked With 1d-Amps Simulation, Ming-Lang Tseng, Malek Gassoumi, Nima Ghadiri Jan 2023

Analysis Of Degradation Of Sb2se3 Thin Film Solar Cells Deploying A Time-Dependent Approach Linked With 1d-Amps Simulation, Ming-Lang Tseng, Malek Gassoumi, Nima Ghadiri

Articles

In this paper, we have developed a time-dependent model to study defect growth in the absorber layer of Sb2Se3 thin film solar cells. This model has been integrated with the AMPS-1D simulation platform to investigate the impact of increasing defect density at different positions within the Sb2Se3 layer on the electrical parameters of the solar cell. We adopted the Gloeckler standard model for thin films in AMPS to represent Sb2Se3 materials. The study focuses on tracking the degradation of device performance parameters as donor-like mid-gap states accumulate in the Sb2Se3 layer over time. We monitored the variation of key electrical …


Charge Transport, Conductivity And Seebeck Coefficient In Pristine And Tcnq Loaded Preferentially Grown Metal Organic Frameworks, Xin Chen, Kai Zhang, Zeinab Mohammed Hassan, Engelbert Redel, Helmut Baumgart Jan 2021

Charge Transport, Conductivity And Seebeck Coefficient In Pristine And Tcnq Loaded Preferentially Grown Metal Organic Frameworks, Xin Chen, Kai Zhang, Zeinab Mohammed Hassan, Engelbert Redel, Helmut Baumgart

Electrical & Computer Engineering Faculty Publications

This investigation on Metal-Organic Framework (MOF) HUKUST-1 films focuses on comparing the undoped pristine state and with the case of doping by TCNQ infiltration of the MOF pore structure. We have determined the temperature dependent charge transport and p-type conductivity for HKUST-1 films. Furthermore, the electrical conductivity and the current-voltage characteristics have been characterized in detail. Because the most common forms of MOFs, bulk MOF powders, do not lend themselves easily to electrical characterization investigations, here in this study the electrical measurements were performed on dense, compact surface-anchored metal-organic framework (SURMOF) films. These monolithic, well-defined, and (001) preferentially oriented MOF …


Gamma-Ray Radiation Effects In Graphene-Based Transistors With H-Bn Nanometer Film Substrates, E. J. Cazalas, Michael R. Hogsed, S. R. Vangala, Michael R. Snure, John W. Mcclory Nov 2019

Gamma-Ray Radiation Effects In Graphene-Based Transistors With H-Bn Nanometer Film Substrates, E. J. Cazalas, Michael R. Hogsed, S. R. Vangala, Michael R. Snure, John W. Mcclory

Faculty Publications

Radiation effects on graphene field effect transistors (GFETs) with hexagonal boron nitride (h-BN) thin film substrates are investigated using 60Co gamma-ray radiation. This study examines the radiation response using many samples with varying h-BN film thicknesses (1.6 and 20 nm thickness) and graphene channel lengths (5 and 10 μm). These samples were exposed to a total ionizing dose of approximately 1 Mrad(Si). I-V measurements were taken at fixed time intervals between irradiations and postirradiation. Dirac point voltage and current are extracted from the I-V measurements, as well as mobility, Dirac voltage hysteresis, and the total number of GFETs that remain …


Nanostructure Evolution Of Magnetron Sputtered Hydrogenated Silicon Thin Films, Dipendra Adhikari, Maxwell M. Junda, Sylvain X. Marsillac, Robert W. Collins, Nikolas J. Podraza Aug 2017

Nanostructure Evolution Of Magnetron Sputtered Hydrogenated Silicon Thin Films, Dipendra Adhikari, Maxwell M. Junda, Sylvain X. Marsillac, Robert W. Collins, Nikolas J. Podraza

Electrical & Computer Engineering Faculty Publications

Hydrogenated silicon (Si:H) thin films have been prepared by radio frequency (RF) magnetron sputtering. The effect of hydrogen gas concentration during sputtering on the resultant film structural and optical properties has been investigated by real time spectroscopic ellipsometry (RTSE) and grazing incidence x-ray diffraction (GIXRD). The analysis of in-situ RTSE data collected during sputter deposition tracks the evolution of surface roughness and film bulk layer thickness with time. Growth evolution diagrams depicting amorphous, nanocrystalline and mixed-phase regions for low and high deposition rate Si:H are constructed and the effects of process parameter (hydrogen gas concentration, total pressure and RF power) …


The Ph Sensing Properties Of Rf Sputtered Ruo2 Thin-Film Prepared Using Different Ar/O2 Flow Ratio, Ali Sardarinejad, Devendra Kumar Maurya, Kamal Alameh Jan 2015

The Ph Sensing Properties Of Rf Sputtered Ruo2 Thin-Film Prepared Using Different Ar/O2 Flow Ratio, Ali Sardarinejad, Devendra Kumar Maurya, Kamal Alameh

Research outputs 2014 to 2021

The influence of the Ar/O2 gas ratio during radio frequency (RF) sputtering of the RuO2 sensing electrode on the pH sensing performance is investigated. The developed pH sensor consists in an RF sputtered ruthenium oxide thin-film sensing electrode, in conjunction with an electroplated Ag/AgCl reference electrode. The performance and characterization of the developed pH sensors in terms of sensitivity, response time, stability, reversibility, and hysteresis are investigated. Experimental results show that the pH sensor exhibits super-Nernstian slopes in the range of 64.33-73.83 mV/pH for Ar/O2 gas ratio between 10/0-7/3. In particular, the best pH sensing performance, in …


Investigation Of Nanoporous Thin-Film Alumina Templates, Biswajit Das May 2004

Investigation Of Nanoporous Thin-Film Alumina Templates, Biswajit Das

Electrical & Computer Engineering Faculty Research

This paper presents the results of a systematic study of the fabrication of thin-film alumina templates on silicon and other substrates. Such templates are of significant interest for the low-cost implementation of semiconductor and metal nanostructure arrays. In addition, thin-film alumina templates on silicon have the potential for nanostructure integration with silicon electronics. Formation of thin-film alumina templates on silicon substrates was investigated under different fabrication conditions, and the dependence of pore morphology and pore formation rate on process parameters was evaluated. In addition, process conditions for improved pore size distribution and periodicity were determined. The template/silicon interface, important for …


Low Cost Schottky Barrier Solar Cells Fabricated On Cdse And Sb2S3 Films Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal Oct 1994

Low Cost Schottky Barrier Solar Cells Fabricated On Cdse And Sb2S3 Films Chemically Deposited With Silicotungstic Acid, O. Savadogo, K. C. Mandal

Faculty Publications

No abstract provided.


Low‐Cost Technique For Preparing N‐Sb2S3/P‐Si Heterojunction Solar Cells, O. Savadogo, K. C. Mandal Jul 1993

Low‐Cost Technique For Preparing N‐Sb2S3/P‐Si Heterojunction Solar Cells, O. Savadogo, K. C. Mandal

Faculty Publications

No abstract provided.


Electrical Properties Of Hydrogenated Diamond, Sacharia Albin, Linwood Watkins Jan 1990

Electrical Properties Of Hydrogenated Diamond, Sacharia Albin, Linwood Watkins

Electrical & Computer Engineering Faculty Publications

Hydrogen passivation of deep traps in diamond is demonstrated. Current‐voltage (IV) characteristics of polycrystalline thin film and bulk diamond were studied before and after hydrogenation. On hydrogenation, all the samples showed several orders of magnitude increase in conductivity. Hydrogenation was carried out under controlled conditions to study the changes in the IV characteristics of the samples. The concentration of uncompensated traps was varied systematically by hydrogenation. The concentration of electrically active hydrogen was determined from the IV data. It is shown that hydrogenation is an alternative to deep‐level transient spectroscopy, suitable for …