bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimized design of carbon nanotube field-effect transistor using Taguchi method for enhanced current ratio performance
Authors: Abdul Hadi M F , Hussin H , Muhamad M , Abd Wahab Y 
Published: May 2024

Abstract
Presently, the integrated circuit (IC) industry grapples with obstacles in downsizing MOSFET technology further, hindered by its inherent physical constraints. Therefore, the substitution of silicon with carbon nanotubes (CNTs) holds promise for paving a novel path in semiconductor industries, driven by their diminutive dimensions and superior electrical properties. Hence, this project employed SILVACO ATLAS software in conjunction with the Taguchi method to refine a CNTFET design for optimal performance. In this work, response variables consists of on-current (Ion), current ratio (Ion/Ioff) and threshold voltage (Vth) are extracted. In this particular design, the Taguchi method was employed to ascertain the most effective combination of design parameters and materials to achieve optimal CNTFET performance, as assessed by the three key response variables. The design parameter and material that had been chosen were the diameter of carbon nanotube (Dcnt), dielectric material (K) and oxide thickness (tox). Each of the design parameters and material had three different values. For K, the values are 3.9 (SiO2), 25 (ZrO2) and 80 (TiO2). While for Dcnt and tox, the values are 4.0 nm, 6.0 nm, 8.0 nm and 2.0 nm, 4.0 nm, 6.0 nm respectively. According to the Taguchi optimization findings, the ideal combination of parameters comprises a CNT diameter of 4.0 nm, an oxide thickness of 2.0 nm, and the use of TiO2 (80) as the dielectric material. The ANOVA analysis underscores the significance of prioritizing optimization efforts towards the CNT diameter parameter. This is attributed to its substantial contribution, accounting for 93.55% of the variation in the Ion/Ioff value, surpassing the influence of dielectric materials and oxide thickness.
Super-resolution imaging and autofocusing via compressive-sensing-based twin-image-free holography
Authors: Zhang Cheng , Shi Jisen , Zhou Jiaxuan , Han Peng , Zhou Hao , Yang Hairong , Shen Chuan , Wei Sui 
Published: May 2024

Abstract
This paper presents an iterative reconstruction framework for super-resolution imaging and autofocusing via compressive-sensing-based twin-image-free holography (SRI-AF-CS-TIFH) for 3D (multi-plane) object in compressed holographic imaging. In our proposed framework, in the first step, the Hough transform edge detection method is incorporated into the eigenvalue-based autofocusing algorithm (dubbed as EIG-AF-Hough) to accurately estimate the focus distances for each plane of multi-plane objects from the snapshot measurements; In the second step, nonlinear optimization is used to achieve the super-resolution reconstruction from the same snapshot measurements. Experimental results demonstrate the effectiveness of our proposed framework for achieving autofocusing and super-resolution in compressed holographic imaging simultaneously in both simulated and real holographic scenarios.
The synthesis and application of L-cysteine graphene quantum dots for quantitative analysis of nitrite content in water
Authors: Jin Li , Li Lan , Xu Feng , Zhang Jianpo 
Published: May 2024

Abstract
The limit standard of nitrite content in drinking water is an internationally recognized safety indicator. Some fluorescence analysis methods used for quantitative analysis of nitrite suffered from low anti-interference performance and inadequate specificity. In this article, L-cysteine graphene quantum dots have been synthesized and used to built a sensor system of ratiometric fluorescence with CdTe quantum dots. The L-cysteine graphene quantum dots were characterized by TEM and XPS. Results shown that the size of product is about 2 nm with homogeneous dispersion and a interplanar distance 0.235 nm, and there were hydroxyl, carboxyl, amino and sulfhydryl groups on its surface. Also, according to the linear association between nitrite concentrations and the ratio of fluorescence intensities at 421 and 570 nm (F421 nm/F570 nm), the quantitative analysis of nitrite in water has been realized, of which the linear range was 7.25–72.5 nmol/l, and the lowest detection limit was 3.012 nmol/l. This method with high sensitivity, selectivity, and anti-interference ability might be applied to analyze of nitrite in water quantitatively.
Cryptographic algorithm for multi-path distribution of entangled states of orbital angular momentum based on Fibonacci values
Authors: Lai Hong , Wan Linchun 
Published: May 2024

Abstract
Drawing inspiration from the Fibonacci sequence and its complementary Lucas sequence, this paper introduces an innovative encryption and decryption algorithm tailored for multi-path quantum key distribution. The algorithm capitalizes on the high-quality orbital angular momentum entangled states, harnessing the mathematical elegance of Fibonacci numbers to construct block diagonal matrices. These matrices serve as the foundation for the simultaneous execution of key distribution across multiple communication paths in a structured block distribution format. The encryption process is facilitated through a combination of linear mappings, employing specific transition matrices to manage the cryptographic flow. The security underpinning of this method is firmly rooted in the Heisenberg Uncertainty Principle, a fundamental tenet of quantum mechanics, which ensures the confidentiality and integrity of the quantum communication channel. This approach paves the way for a novel encryption paradigm, fortifying the security framework of quantum communication networks.
Determining absolute VUV fluxes for assessing the relevance of photon-surface interaction in ion sources
Authors: Friedl R , Frohler-Bachus C , Fantz U 
Published: May 2024

Abstract
A portable device was developed to quantify VUV fluxes flexibly at ion source setups. It consists of a VUV sensitive photodiode and optical filters for wavelength selection and is calibrated against a VUV spectrometer down to 46 nm for a variety of discharge gases, including Ar, N2, O2 and H2. It was applied to the negative hydrogen ion source at BATMAN Upgrade to quantify the VUV radiation emitted by the driver as well as in front of the extraction surface (plasma grid, PG). The combined VUV fluxes impinging on the PG with photon energies larger than 6.6 eV has a comparable magnitude as the ion flux. It could be shown that the recently confirmed influence of the ion source plasma on the surface work function of the PG can at least partly be ascribed to the VUV radiation from the driver and that photo-emitted electrons from the PG should not play a role in the sheath physics.
3D Self-Consistent Full Wave – PIC Models for Investigating Space-Resolved ECR Plasma Properties
Authors: Mishra B , Galatà A , Pidatella A , Torrisi G , Salvia C , Mauro GS , Naselli E , Rácz R , Biri S , Mascali D 
Published: May 2024

Abstract
Simulations are a powerful method to study the correlation between output beams and internal dynamics of electron cyclotron resonance ion sources (ECRIS), which involve a complex interplay between injected power, RF frequency, gas type and pressure. We present here some details on 3D full-wave Particle-in-Cell (PIC) code suites that can simulate electron and ion dynamics self-consistently in an ECR plasma. Preliminary runs of the simulation show an encouraging match with experimental data which acts as a benchmark for the PIC codes and highlights its potential for fundamental and applied interdisciplinary plasma research.
Advances in Particle-In-Cell Modeling of Low-Temperature Plasma Ion Sources
Authors: Veitzer Seth A. , Main Daniel 
Published: May 2024

Abstract
Ion sources that use low-temperature plasma (LTP) discharges are used in a variety of applications, including ion implantation, mass spectrometry, and plasma processing. In recent years there has been a growing interest in using particle-in-cell (PIC) modeling to improve the performance and optimization of LTP-based ion sources. PIC modeling is a powerful tool for simulating the dynamics of plasmas because it accurately models the effects of self-consistent fields, charge deposition, plasma chemistry, magnetic confinement, and accurate sheath physics. However, PIC simulations can be computationally demanding, especially for 3D systems.
We present new advances in PIC modeling of LTP ion sources. We focus on two key challenges: 1. Efficient and accurate modeling of plasma chemistry: Plasma chemistry is a complex process that can have a significant impact on the performance of LTP ion sources. We demonstrate using global models to reduce the computational cost of plasma chemistry simulations, and diagnostics for understanding the physics of those reactions. 2. Energy-conserving PIC models: PIC simulations typically require a fine spatial grid in order to resolve the Debye length. This can be computationally expensive, especially for 3D systems. We present a new energy-conserving PIC model implementation that allows us to perform simulations without resolving the Debye length. We validate these methods on two different types of LTP ion sources: a Bernas source and a Penning source. Our results show that these methods can significantly improve the efficiency and accuracy of PIC simulations of LTP-based ion sources.
Design improvements to the SNS ion source and diagnostics
Authors: Welton Robert , Han Baoxi , Kalvas Taneli , Stinson Chris , Andzulis Vic , Terszakowec Greg , Willis Dave , Tarvainen Olli 
Published: May 2024

Abstract
The U.S. Spallation Neutron Source (SNS) is a state-of-the-art neutron scattering facility delivering the world’s most intense pulsed-neutron beams to a wide array of instruments which are used to conduct investigations in many fields of science and engineering. The accelerator system is fed by an RF-driven, multicusp, H− ion source which nominally provides pulsed beam currents of 50-60 mA (1ms, 60Hz). This report provides a discussion of ongoing design improvements to the SNS ion source and Low Energy Beam Transport (LEBT) as well as diagnostic upgrades undertaken since the previous ICIS conference. These improvements include (i) simple mechanical modifications to the source outlet aperture which resulted in dramatically increased extracted beam current and comparable or lower emittance at similar beam currents, (ii) design improvements to the LEBT chopper target which will enable full power beam-dumping during physics studies, (iii) refinement of the SNS Allison emittance scanner that has enabled the first reliable LEBT beam measurements at full beam power (65kV, 50-100mA, 1ms, 60Hz) on the SNS ion source test stand and (iv) the implementation of a thermal imaging camera for the monitoring the LEBT electrode temperatures. (v) The design of an advanced Cs system, capable of more efficient Cs utilization with significantly lower Cs losses from the source is also presented. Mechanical details, computational simulations and experimental results are discussed within the context of these improvements.
Development of a novel Internal Radio-frequency Ion Source for Cyclotrons (IRISC)
Authors: Leon M , Calvo P , Eriksson T , Estévez A , García-Tabarés L , Gavela D , Obradors D , Oliver C , Pérez J M , Toral F , Varela R 
Published: May 2024

Abstract
IRISC (Internal Radio-frequency Ion Source for Cyclotrons) is an innovative design of an internal ion source, primarily for producing H− ions, in which 2.45 GHz radio-frequency power is supplied to its electrodes for achieving electron emission. Theoretical work indicates that lower electrode sputtering and higher extraction efficiency of H− may be achieved as compared to its standard cold-cathode direct current (DC) Penning Ionization Gauge (PIG) counterparts. If achieved, IRISC would arise as a ground-breaking ion source with significant importance for compact cyclotrons. IRISC dimensions have been matched to CIEMAT’s AMIT cold-cathode DC PIG ion source so that, in the future, side-by-side testing can be carried out and, eventually, both types can be used in AMIT cyclotrons. This contribution presents IRISC key design aspects, outcome from simulations, its dedicated test bench and first low-power test results from a prototype.
TRIUMF’s H-/D- Ion Source Development to Date
Authors: Jayamanna K. , Ames F. , Bylinskii Y. , Lovera M. , Louie D. , Minato B. , Portilla D. , Saminathan S. 
Published: May 2024

Abstract
The TRIUMF Stable Ion Source group has been developing negative and positive ion sources for decades, including a few arc-discharge H-/D- ion sources and a microwave-driven H-/D- ion source for medical cyclotrons [1] and other applications. The smallest ion source with a 125 cc plasma chamber can produce up to 5 mA continuously. The largest ion source with a 1200 cc plasma chamber is able to produce 60 mA with increased arc power and enhanced magnetic confinement. The filament-less microwave ion source is capable of producing up to 5 mA H- current for years without any manual intervention. A historical overview of H-/D- source development at TRIUMF is presented. A summary of employed optical and diagnostics components is also presented
Design for an 18 GHz Open Hexapole Electron Cyclotron Resonance Ion Source
Authors: Vondrasek R. C. , McLain J. , Scott R. H. 
Published: May 2024

Abstract
Responding to a request by the user community for higher beam intensities, an upgrade of the Argonne National Laboratory ECR2 ion source is in progress. The upgrade has three main constraints: 1) The overall source architecture as defined by the solenoid coils cannot change, 2) radial access to the plasma chamber has to be maintained, and 3) the amount of time the source can be shut down for hardware installation is < 2 months. A new NdFeB open hexapole is projected to produce a 1.19 T wall field (r = 38.1 mm) with six radial slots (6.35 mm x 91.2 mm) allowing solid material access and ∼120 l/s of pumping to the plasma chamber. The axial magnetic fields will be enhanced with a vanadium permendur plug and optimization of the iron resulting in a magnetic field at injection Binj of 2.4 T, magnetic field at center Bmin of 0.4 T, and magnetic field at extraction Bext of 1.0 T and magnetic gradients Bgrad of 5.9 T/m for 14.5 GHz and 7.4 T/m for 18 GHz. The plasma is currently heated with multiple-frequency RF provided by two traveling wave tube amplifiers (TWTA) operating between 11 and 14.5 GHz and capable of providing 1100 W total power. The new magnetic structure will support 18 GHz operation with RF provided by a new TWTA.
RF Frequency Combining for the ATLAS ECR Ion Sources
Authors: McLain J. , Scott R. H. , Vondrasek R. C. 
Published: May 2024

Abstract
The ECR2 and ECR3 ion sources at the Argonne Tandem Linac Accelerator System (ATLAS) operate with two microwave frequencies, improving their performance over single frequency operation. A typical method for transmitting both microwave frequencies is by having two separate frequency generators with their own corresponding amplifiers. These amplifiers transmit their microwaves into the ion source using separate waveguides. Another method that is investigated is to combine the low power microwave frequencies with a splitter/combiner and input the combined signals into the high-power amplifier, where the combined signal is amplified and transmitted down a single waveguide into the ion source. These different methods for delivering microwave power with multiple frequencies are compared, focusing on the average charge state and the intensities of each of the charge states for an oxygen plasma produced by the ECR2 ion source.
This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357. This research used resources of ANL’s ATLAS facility, which is a DOE Office of Science User Facility.
Extraction experiments at the UNIST electron beam ion trap for highly charged ion studies
Authors: Han Je Hwan , Park Sung Nam , Shin Bok Kyun , Yoo Kyounghun , Cosgun Emre , Kwak Donghyun , Chung Moses 
Published: May 2024

Abstract
Highly charged ions (HCIs) are currently utilized in numerous fundamental and applied sciences, including astrophysics, dark matter search, optical clocks, semiconductor lithography, and quantum dot fabrication, to name just a few examples. At Ulsan National Institute of Science and Technology (UNIST), a tabletop electron beam ion trap (EBIT) has been developed for creating and studying HCIs. The UNIST-EBIT compresses the electron beam by 72 permanent magnets (up to 0.84 T) and produces up to He-like Ar ions. The primary objective of the UNIST-EBIT is to obtain X-ray spectrum data essential in astrophysics. Meanwhile, optical clocks based on HCIs are receiving significant attention from the scientific community. The UNIST-EBIT can also provide various HCIs for optical clock applications. For this purpose, designing an extraction beamline along with an initial extraction experiment of Ar ions from the EBIT is underway. To extract Ar ions, we consider constructing an automatic control system with EPICS. In this work, we present the recent progress of the UNIST-EBIT for extraction experiments.
Intense vanadium ion beam production for super-heavy element research experiments
Authors: Higurashi Y , Saquilayan G Q , Ohnishi J , Nagatomo T 
Published: May 2024

Abstract
Long-term production of an intense 51V13+ ion beam was imperative for synthesizing a new element (Z=119) at RIKEN. We systematically measured the beam intensity as a function of microwave power and material consumption rate for effectively producing an intense beam. Consequently, we generated a 1 emA of 51V13+ ion beam at an injected microwave power and extraction voltage of 3.5 kW and 12.6 kV, respectively.
High-Current Capability and Upgrades of the EBIS/T Charge-Breeding System in the Reaccelerator at the Facility for Rare-Isotope Beams
Authors: Lapierre A. , Son H.-J. , Ringle R. , Schwarz S. , Villari A. C. C. 
Published: May 2024

Abstract
The Reaccelerator (ReA) of the Facility for Rare-Isotope Beams (FRIB) at Michigan State University uses a Beam Cooler/Buncher (BCB) and an Electron-Beam Ion Trap (EBIT) as a charge-breeding injector system. The rare isotopes produced by In-flight Separation are selected by the Advanced Rare Isotope Separator (ARIS) and stopped in a helium gas cell. Long-lived and stable-isotope beams can also be extracted from a Batch-Mode Ion Source (BMIS). The continuous beams transported at low energy to ReA are injected into the BCB. The pulsed beams are then injected into the EBIT, charge bred, ejected, and accelerated by ReA’s LINAC. The EBIT electron current (300 - 600 mA) is a factor that limits its capacity to ∼2×1010 elementary charges, which restricts the maximum EBIT-extracted rates to less than 2×1010 particles per second for light ions. An upgrade of the EBIT electron gun is expected to provide 2 A in current. In parallel, a High-Current Electron-Beam Ion Source (HCEBIS) is being commissioned. The HCEBIS can presently provide an electron current of 2 A. An upgrade will increase the current to 4 A. The implementation of these two upgrades is expected to allow for maximum rates to be ∼1011 pps, compatible with FRIB projected rates and user demands. We review the high-current capabilities and upgrades of ReA’s charge-breeding system.
FEBIAD ionization development via a web-app for multidimensional characterization
Authors: Maldonado Millán F , Babcock C , Day Goodacre T , Kiy S , Gottberg A 
Published: May 2024

Abstract
The ISAC-FEBIAD is an electron impact ion source typically used to ionize radioactive molecules or isotopes of elements beyond the reach of either surface or laser ion sources. The FEBIAD’s key tuning parameters are the cathode temperature defining the number of electrons created; the anode voltage establishing the electron energy; and the magnetic field controlling the electron density inside the anode volume. However, these parameters are typically scanned in a small and limited range when optimizing the source. Recent investigations have shown the need to explore the entire range of operational values accessible by the power supplies, not only due to the intrinsic variations from source to source but also to operate the source at optimal settings. To address this, a scanning algorithm has been implemented as a web interface thanks to the High-Level-Application (HLA) infrastructure available at TRIUMF. The ion beam intensity during both offline and online commissioning of the web app are presented here as contour plots. The optimal settings found for stable 20Ne are confirmed as the optimal settings for radioactive 18Ne. The main takeaway, however, is that the optimal ion source parameters differ between singly-charged, doubly-charged, and molecular species. This development demonstrate and facilitate the need for element and charge state-specific parameter optimization. Additionally, the results highlight the possibility of parameter optimization to enhance the ratio of the species of interest to co-ionized contamination.
Development of an Image Analysis Method for Pepperpot Emittance Monitors
Authors: Morita Y , Nagatomo T , Nakashima Y 
Published: May 2024

Abstract
At the RIKEN Nishina Center for Accelerator-Based Science, we developed a pepperpot emittance monitor using a method that can change the distance between the pepperpot mask and the screen. The accuracy can be improved by correctly identifying the beam’s position at a close range followed by the increase of the distance; however, if the distance is increased excessively, the position matching will be difficult. To solve this problem, we developed a method for tracking continuous changes on a screen using optical flow. Using this method, the distance between the pepperpot mask and screen could be extended without plotting in the wrong area in the phase space, and the emittance measurement accuracy was successfully improved by more than 10%. This development will enable beam transport simulations to be performed more accurately.
Beam Emittance Growth of Highly Charged Ion Beams from the RIKEN 28-GHz SC-ECRIS
Authors: Saquilayan G Q , Nagatomo T , Higurashi Y , Ohnishi J , Nakagawa T , Kamigaito O 
Published: May 2024

Abstract
Different factors that affect the beam emittance of highly charged ions extracted from the RIKEN 28-GHz superconducting ECR ion source have been investigated. Since the ion source parameters, space charge effects and various beamline components directly affect the beam quality, it was attempted to experimentally determine the different components that contribute to the beam emittance growth. From the experimental measurements, a beam emittance defined by the ion source has been evaluated based on a simple model calculation for space charge induced beam emittance. Ion beams using 40Ar11+ and 136Xe20+ ions were generated, and the beam emittance from the ion source and space charge were fitted from the experimental results. These parameters will be used to further evaluate the relationship between the extracted beam emittances and the ECR ion source parameters.