Journal of the Korean Physical Society最新文献_第6页

Magnetic design of the K-4GSR combined-function booster dipole magnet K-4GSR多功能升压偶极磁体的磁性设计

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-17 DOI: 10.1007/s40042-026-01621-9

Inwoo Chun, Beom Jun Kim, Seo Hyeon Ahn, Garam Hahn, Young Gyu Jung, Dong Eon Kim

引用次数: 0

Three-dimensional position reconstruction of a cascade gamma ray-emitting source based on geometric back-projection through the angle of incidence 基于入射角几何背投影的级联伽马射线源三维位置重建

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-17 DOI: 10.1007/s40042-026-01645-1

Leonid L. Nkuba, Enock M. Mwita, Innocent J. Junior, Elisha E. Edmund, Innocent J. Lugendo

{"title":"Three-dimensional position reconstruction of a cascade gamma ray-emitting source based on geometric back-projection through the angle of incidence","authors":"Leonid L. Nkuba, Enock M. Mwita, Innocent J. Junior, Elisha E. Edmund, Innocent J. Lugendo","doi":"10.1007/s40042-026-01645-1","DOIUrl":"10.1007/s40042-026-01645-1","url":null,"abstract":"<div>A novel technique has been developed to determine the three-dimensional position of a source emitting multiple cascade γ-rays with sub-millimeter accuracy using dual-layered GSO (Ce) scintillation detectors. This method reconstructs the source position by processing filtered energy and detector hit positions through a back-projection algorithm along the paths of incident γ-rays. The detector array and an 111In-ion point source at five locations within the central detection volume were simulated using the GATE Monte Carlo framework. For a source at the detector center (0, 0, 0), the reconstructed coordinates are − 0.001 mm, − 0.001 mm, and − 0.001 mm along X, Y, and Z. This indicates that the reconstructed source centroid was centrally located and well within the spatial resolution limits of the detector system. For other simulated source positions, the reconstructed coordinates matched approximately 99.8% of the actual simulated positions, although some positions varied between 70.9% and 125% of the true values. Except for source at the center, other source positions were reported with uncertainty ranging from 0.006 × 10–3 mm to ± 5.480 × 10–3 mm. While reconstruction at the transaxial and axial edges is less precise due to limited valid coincidence events, the results demonstrate the method’s robustness. The achieved reconstruction precision indicates potential applications in nuclear medicine, nuclear security, radioactive waste assay, and proton beam therapy.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 4","pages":"325 - 334"},"PeriodicalIF":1.0,"publicationDate":"2026-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40042-026-01645-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148704207","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Defect evolution comparison between He+ and He2+ ions irradiation on graphene He+和He2+离子辐照石墨烯缺陷演化比较

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-15 DOI: 10.1007/s40042-026-01635-3

Junhyeok Seo, Sunmog Yeo, Young Jun Yoon, Kibeom Kim

{"title":"Defect evolution comparison between He+ and He2+ ions irradiation on graphene","authors":"Junhyeok Seo, Sunmog Yeo, Young Jun Yoon, Kibeom Kim","doi":"10.1007/s40042-026-01635-3","DOIUrl":"10.1007/s40042-026-01635-3","url":null,"abstract":"<div>This study investigates the role of the projectile's charge state in the defect engineering of graphene using ion beams. A comparison was made between defects induced by He+ and He2+ ions at an identical kinetic energy of 120 keV. Raman spectroscopy analysis showed that He2+ ions generated a higher defect density, ranging from 40 to 65%, compared to He⁺ ions. To investigate how this defect difference impacts device performance, we fabricated and tested chemiresistive gas sensors, where devices irradiated with He2+ showed improved sensitivity to hydrogen. The observation of higher defect generation for He2+ can be explained by the absence of electron screening, which is present for the He⁺ ion. This condition could increase the Coulomb interaction with target carbon nuclei, consistent with a larger Rutherford scattering cross-section. The results indicate that, even within the same ion species, the ion charge state can serve as an additional parameter for modifying the properties of graphene-based devices.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 on","pages":"472 - 476"},"PeriodicalIF":1.0,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40042-026-01635-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148807485","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Study of the influence of implant material on magnetocardiography measurements using SQUID sensors 植入材料对SQUID传感器心脏磁图测量影响的研究

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-13 DOI: 10.1007/s40042-026-01640-6

Ho Seong Lee, Jae Hyun Ahn, Yong Hwan Kim

{"title":"Study of the influence of implant material on magnetocardiography measurements using SQUID sensors","authors":"Ho Seong Lee, Jae Hyun Ahn, Yong Hwan Kim","doi":"10.1007/s40042-026-01640-6","DOIUrl":"10.1007/s40042-026-01640-6","url":null,"abstract":"<div>A magnetocardiography (MCG) system is a medical device that diagnoses cardiac disease by measuring magnetic fields generated from electric currents flowing through the myocardium. However, the accuracy of measurement data can be degraded if strong magnetic materials are present or magnetic field changes occur near the MCG system. With the widespread use of implants, the number of patients with metallic implants is increasing, but there is a lack of in-depth research on the potential impact of implant materials on the results of the MCG examination. This study aims to analyze the effect of implant materials on MCG measurements and establish relevant criteria. In this study, a 96-channel MCG system employing Superconducting Quantum Interference Device (SQUID) sensors, specifically first-order gradiometers based on the Double Relaxation Oscillation SQUID method, and a magnetically shielded room were utilized. Titanium-6Aluminum-4Vanadium ELI was selected as the representative implant material sample. Experiments were conducted under extreme conditions, where a sample significantly larger than an actual implant was placed as close as possible to the sensors. As a result, when the implant material was at the minimum distance to the sensor, the noise increase was approximately 0.7 fT/√Hz, which satisfies the sensitivity criteria for MCG. Furthermore, since these results were obtained under severely adverse conditions designed to maximize the noise impact, it is anticipated that the effect would be even more negligible in actual clinical settings. In conclusion, it was confirmed that common implant materials have little to no effect on MCG measurements.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 2","pages":"204 - 211"},"PeriodicalIF":1.0,"publicationDate":"2026-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148366079","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of background pressure on beam extraction and focusing dynamics in a small PIG ion source 背景压力对小型PIG离子源中光束提取和聚焦动力学的影响

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-10 DOI: 10.1007/s40042-026-01636-2

Jiseong Nam, Kyoung-Jae Chung

{"title":"Influence of background pressure on beam extraction and focusing dynamics in a small PIG ion source","authors":"Jiseong Nam, Kyoung-Jae Chung","doi":"10.1007/s40042-026-01636-2","DOIUrl":"10.1007/s40042-026-01636-2","url":null,"abstract":"<div>Vacuum degradation in the beam device is a critical concern in high-precision ion beam processing, as it perturbs beam optics and reduces energy efficiency. While pressure effects in the transport region are mitigated by space charge compensation and charge exchanges, the dynamics in the extraction region of low-energy sources under elevated vacuum conditions remain insufficiently understood. In this paper, we experimentally investigate the influence of background pressure on beam focusing and extraction efficiency in a small penning ion gauge (PIG) ion source, where the extraction section constitutes a dominant part of the beamline. Our results reveal that, under elevated pressure conditions, the current impinging on the suppression electrode increases with higher suppression voltages—a trend contrary to the low-pressure conditions. We demonstrate that this current loss increment is attributed to the trapping of low-energy ions generated via charge exchange and momentum transfer, rather than to the conventional electrostatic over-focusing mechanism. These findings indicate that elevated background pressures primarily accelerate device degradation through collision-induced beam loss, necessitating rigorous vacuum management for stable operation.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 on","pages":"457 - 461"},"PeriodicalIF":1.0,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40042-026-01636-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148807402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Plasma-free KOH-based surface activation for enhanced hybrid bonding strength 无等离子体koh表面活化增强杂化键合强度

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-10 DOI: 10.1007/s40042-026-01633-5

Youngjoon Cha, Gyeongyeol Lee, An Hoang-Thuy Nguyen, Rino Choi

引用次数: 0

Specific heat investigation of superconducting properties in 2H-NbSe2 single crystals 2H-NbSe2单晶超导性能的比热研究

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-10 DOI: 10.1007/s40042-026-01632-6

Joo Chan Kim, Yeong Uk Choi, Su Min Lee, Jong Yeon Kim, Jung Jin Park, Min Su Yeo, Jong Hun Kim, Jong Hoon Jung

{"title":"Specific heat investigation of superconducting properties in 2H-NbSe2 single crystals","authors":"Joo Chan Kim, Yeong Uk Choi, Su Min Lee, Jong Yeon Kim, Jung Jin Park, Min Su Yeo, Jong Hun Kim, Jong Hoon Jung","doi":"10.1007/s40042-026-01632-6","DOIUrl":"10.1007/s40042-026-01632-6","url":null,"abstract":"<div>We report on the crystal growth and superconducting properties of the transition-metal dichalcogenide 2H-NbSe2. Millimeter-scale 2H-NbSe2 single crystals with well-defined hexagonal platelets were grown by chemical vapor transport with iodine (I2) as the transport agent. Rietveld analysis of X-ray powder diffraction confirms the single-phase P63/mmc space group with a = b = 3.443 Å and c = 12.542 Å. Electrical transport and magnetic measurements confirm bulk superconductivity (Tc = 7.06 K), coexistence of charge density wave order (TCDW = 33 K), and nearly ideal diamagnetism (4πχ ~-0.98 at 2 K). Temperature-dependent specific heat shows a clear jump at Tc, which can be analyzed using a two-gap s + s-wave model with different weights. Approximately 97% of the total Sommerfeld coefficient is associated with the larger-gap ((Delta_{1} sim 1.68) meV), while the smaller-gap ((Delta_{2} sim 0.27) meV) accounts for the remaining 3%. This work provides useful quantitative information on multiband superconductivity in 2H-NbSe2 single crystals.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 2","pages":"174 - 181"},"PeriodicalIF":1.0,"publicationDate":"2026-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148366077","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-temperature atomic layer deposition of oriented ZnO thin films on c-plane Al2O3: influence of precursor ratio and growth temperature c面Al2O3上取向ZnO薄膜的低温原子层沉积：前驱体比和生长温度的影响

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-06 DOI: 10.1007/s40042-026-01623-7

Minh-Anh Nguyen Tran, Viet Huong Nguyen, Hung-Anh Tran Vu, Nguyen Dinh Nam, Ngoc Thanh Duong, Anh Tuan Duong, Taegi Kim, Chanyong Hwang

{"title":"Low-temperature atomic layer deposition of oriented ZnO thin films on c-plane Al2O3: influence of precursor ratio and growth temperature","authors":"Minh-Anh Nguyen Tran, Viet Huong Nguyen, Hung-Anh Tran Vu, Nguyen Dinh Nam, Ngoc Thanh Duong, Anh Tuan Duong, Taegi Kim, Chanyong Hwang","doi":"10.1007/s40042-026-01623-7","DOIUrl":"10.1007/s40042-026-01623-7","url":null,"abstract":"<div>In this work, ZnO thin films were deposited on c-plane Al2O3 substrates by atomic layer deposition (ALD) under various growth conditions. The Zn/O feeding time ratios were adjusted from 0.5 to 3.5 at growth temperatures between 120 °C and 300 °C. Films grown at a temperature (Tg) of 200 °C exhibited superior crystallinity and pronounced (200) orientation compared to those grown at lower temperatures, as increased thermal energy promoted more effective surface diffusion and improved atomic arrangement. Raman and photoluminescence analyses revealed well-defined phonon modes and enhanced near-band-edge ultraviolet emission for the film grown at 200 °C with a Zn/O feeding time ratio of 1.5:2, indicating a high degree of structural uniformity and efficient radiative recombination. These findings elucidate how growth temperature and precursor stoichiometry govern the structural and optical quality of ALD-grown ZnO thin films, underscoring the potential of low-temperature ALD for producing high-quality ZnO layers suitable for semiconductor and optoelectronic device applications.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 2","pages":"148 - 156"},"PeriodicalIF":1.0,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148366103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of interface states and series resistance on the electrical and dielectric response of ECR-PECVD SiO₂/p-Si MOS structures 界面态和串联电阻对ECR-PECVD sio2 /p-Si MOS结构电响应和介电响应的影响

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-03 DOI: 10.1007/s40042-026-01638-0

Omar Rejeiba, Alejandro F. Braña de cal, Adel Matoussi

{"title":"Impact of interface states and series resistance on the electrical and dielectric response of ECR-PECVD SiO₂/p-Si MOS structures","authors":"Omar Rejeiba, Alejandro F. Braña de cal, Adel Matoussi","doi":"10.1007/s40042-026-01638-0","DOIUrl":"10.1007/s40042-026-01638-0","url":null,"abstract":"<div>In this work, we examine the electrical and dielectric characteristics of the SiO₂ oxide layer that was produced using the ECR-PECVD method on a p-Si substrate. The frequency range of 100 Hz–1 MHz has been used to record capacitance–voltage (C-Vg) and conductance-voltage (G/ω-Vg) properties. The interface states (Nss) and series resistance (Rs) effects are associated with anomalous peaks in the C-Vg and G-Vg plots. It demonstrates how the capacitance at low frequencies is influenced by the interface state. Because the interface state capacitance decreases with increasing frequency, the effect of series resistance on capacitance becomes noticeable at higher frequencies. In addition, the frequency dependence of dielectric constants (ε’, ε”), dielectric loss tangent (tanδ), electric modulus (M', M''), and the electrical conductivity (σac) is also studied for the Al/SiO2/p-Si (MOS) structure. The double logarithmic σac-w curve shows linear behavior, with its slope around 0.66 to 0.26, and this value of Al/SiO2/p-Si (MOS) structure has a high AC conductivity.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 1","pages":"110 - 119"},"PeriodicalIF":1.0,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

IF 1 4区物理与天体物理

Journal of the Korean Physical Society Pub Date : 2026-04-03 DOI: 10.1007/s40042-026-01634-4

Seungmin Park, Jeongseok Woo, Sangsoo Lee, Geunseop Lee

{"title":"Carbon-related nanometer-scale defects on MoS2 revealed by scanning tunneling microscopy","authors":"Seungmin Park, Jeongseok Woo, Sangsoo Lee, Geunseop Lee","doi":"10.1007/s40042-026-01634-4","DOIUrl":"10.1007/s40042-026-01634-4","url":null,"abstract":"<div>We present a scanning tunneling microscopy (STM) study of nanometer-scale surface defects on the 2H-MoS2(0001) surface of a natural single-crystal mineral. Two dominant types of nanometer-scale defects, denoted as B and D, were ubiquitously observed on freshly exfoliated surfaces in both ultra-high vacuum and ambient environments as well as on intentionally carbon-deposited surfaces. All these observations exclude an extrinsic adsorption-related origin and instead suggest a carbon-related bulk source. The B defects exhibit a pronounced bias-dependent contrast reversal, appearing as bright protrusions at negative sample biases and as dark depressions at positive biases. In contrast, the D defects appear consistently as dark depressions over the entire bias range. The defect population increases gradually over time, supporting an intrinsic bulk reservoir of carbon species. In addition, reversible interconversion between the B and D defects is observed during STM scanning, suggesting that they originate from the same defect species occupying closely related adsorption configurations with similar energies. These results identify carbon impurities as the origin of the most prevalent nanometer-scale surface defects on MoS2 and establish a consistent framework for interpreting their STM contrast and evolution.</div>","PeriodicalId":677,"journal":{"name":"Journal of the Korean Physical Society","volume":"89 1","pages":"101 - 109"},"PeriodicalIF":1.0,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148261752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0