We investigate the potential of epitaxial (001)p-NiO/(0001)n-ZnO heterostructures grown on (0001)sapphire substrates by pulsed laser deposition technique for ultraviolet photodetector application. Our study reveals that in the self-powered mode, these devices can serve as effective photodetectors for the UV-A band (320-400 nm) with response time as short as 400 microseconds. Peak responsivity as high as 5mA/W at zero bias condition have been achieved. These devices also show a very high level of stability under repeated on/off illumination cycles over a long period of time. Furthermore, we find that the response time of these detectors can be controlled from several microseconds to thousands of seconds by applying bias both in the forward and the reverse directions. This persistent photoconductivity effect has been explained in terms of the field induced change in the capture barrier height associated with certain traps located at the junction.
{"title":"p-(001)NiO/n-(0001)ZnO Heterostructures based Ultraviolet Photodetectors","authors":"Amandeep Kaur, Bhabani Prasad Sahoo, Ajoy Biswas, Subhabrata Dhar","doi":"arxiv-2409.11922","DOIUrl":"https://doi.org/arxiv-2409.11922","url":null,"abstract":"We investigate the potential of epitaxial (001)p-NiO/(0001)n-ZnO\u0000heterostructures grown on (0001)sapphire substrates by pulsed laser deposition\u0000technique for ultraviolet photodetector application. Our study reveals that in\u0000the self-powered mode, these devices can serve as effective photodetectors for\u0000the UV-A band (320-400 nm) with response time as short as 400 microseconds.\u0000Peak responsivity as high as 5mA/W at zero bias condition have been achieved.\u0000These devices also show a very high level of stability under repeated on/off\u0000illumination cycles over a long period of time. Furthermore, we find that the\u0000response time of these detectors can be controlled from several microseconds to\u0000thousands of seconds by applying bias both in the forward and the reverse\u0000directions. This persistent photoconductivity effect has been explained in\u0000terms of the field induced change in the capture barrier height associated with\u0000certain traps located at the junction.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"214 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Spin waves (SWs) and their quanta, magnons, play a crucial role in enabling low-power information transfer in future spintronic devices. In backward volume magnetostatic spin waves (BVMSWs), the dispersion relation shows a negative group velocity at low wave numbers due to dipole-dipole interactions and a positive group velocity at high wave numbers, driven by exchange interactions. This duality complicates the analysis of intrinsic interactions by obscuring the clear identification of wave vectors. Here, we offer an innovative approach to distinguish between spin waves with varying wave vectors more effectively by the normal/inverse spin wave Doppler effect. The spin waves at low wave numbers display an inverse Doppler effect because their phase and group velocities are anti-parallel. Conversely, at high wave numbers, a normal Doppler effect occurs due to the parallel alignment of phase and group velocities. Analyzing the spin wave Doppler effect is essential for understanding intrinsic interactions and can also help mitigate serious interference issues in the design of spin logic circuits.
{"title":"Normal/inverse Doppler effect of backward volume magnetostatic spin waves","authors":"Xuhui Su, Dawei Wang, Shaojie Hu","doi":"arxiv-2409.11674","DOIUrl":"https://doi.org/arxiv-2409.11674","url":null,"abstract":"Spin waves (SWs) and their quanta, magnons, play a crucial role in enabling\u0000low-power information transfer in future spintronic devices. In backward volume\u0000magnetostatic spin waves (BVMSWs), the dispersion relation shows a negative\u0000group velocity at low wave numbers due to dipole-dipole interactions and a\u0000positive group velocity at high wave numbers, driven by exchange interactions.\u0000This duality complicates the analysis of intrinsic interactions by obscuring\u0000the clear identification of wave vectors. Here, we offer an innovative approach\u0000to distinguish between spin waves with varying wave vectors more effectively by\u0000the normal/inverse spin wave Doppler effect. The spin waves at low wave numbers\u0000display an inverse Doppler effect because their phase and group velocities are\u0000anti-parallel. Conversely, at high wave numbers, a normal Doppler effect occurs\u0000due to the parallel alignment of phase and group velocities. Analyzing the spin\u0000wave Doppler effect is essential for understanding intrinsic interactions and\u0000can also help mitigate serious interference issues in the design of spin logic\u0000circuits.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"39 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nima Taghipour, Mariona Dalmases, Guy Luke Whitworth, Yongjie Wang, Gerasimos Konstantatos
Achieving low-threshold infrared stimulated emission in solution-processed quantum dots is critical to enable real-life application including photonic integrated circuits (PICs), LIDAR application and optical telecommunication. However, realization of low threshold infrared gain is fundamentally challenging due to high degeneracy of the first emissive state (e.g., 8-fold) and fast Auger recombination. In this letter, we demonstrate ultralow-threshold infrared stimulated emission with an onset of 110 uJ.cm-2 employing cascade charge transfer (CT) in Pb-chalcogenide colloidal quantum dot (CQD) solids. In doing so, we investigate this idea in two different architectures including a mixture of multiband gap CQDs and layer-by-layer (LBL) configuration. Using transient absorption spectroscopy, we show ultrafast cascade CT from large band-gap PbS CQD to small band-gap PbS/PbSSe core/shell CQDs in LBL (~ 2 ps) and mixture (~ 9 ps) configuration. These results indicate the feasibility of using cascade CT as an efficient method to reduce optical gain threshold in CQD solid films.
{"title":"Ultrafast cascade charge transfer in multi bandgap colloidal quantum dot solids enables threshold reduction for optical gain and stimulated emission","authors":"Nima Taghipour, Mariona Dalmases, Guy Luke Whitworth, Yongjie Wang, Gerasimos Konstantatos","doi":"arxiv-2409.11982","DOIUrl":"https://doi.org/arxiv-2409.11982","url":null,"abstract":"Achieving low-threshold infrared stimulated emission in solution-processed\u0000quantum dots is critical to enable real-life application including photonic\u0000integrated circuits (PICs), LIDAR application and optical telecommunication.\u0000However, realization of low threshold infrared gain is fundamentally\u0000challenging due to high degeneracy of the first emissive state (e.g., 8-fold)\u0000and fast Auger recombination. In this letter, we demonstrate ultralow-threshold\u0000infrared stimulated emission with an onset of 110 uJ.cm-2 employing cascade\u0000charge transfer (CT) in Pb-chalcogenide colloidal quantum dot (CQD) solids. In\u0000doing so, we investigate this idea in two different architectures including a\u0000mixture of multiband gap CQDs and layer-by-layer (LBL) configuration. Using\u0000transient absorption spectroscopy, we show ultrafast cascade CT from large\u0000band-gap PbS CQD to small band-gap PbS/PbSSe core/shell CQDs in LBL (~ 2 ps)\u0000and mixture (~ 9 ps) configuration. These results indicate the feasibility of\u0000using cascade CT as an efficient method to reduce optical gain threshold in CQD\u0000solid films.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"18 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Back-end-of-line (BEOL) logic integration is emerging as a complementary scaling path to supplement front-end-of-line (FEOL) Silicon. Among various options for BEOL logic, Carbon Nanotube Field-Effect Transistors (CNFETs) have been integrated within commercial silicon foundries, and complex CNFET circuits (e.g., RISC-V core, SRAM arrays) have been demonstrated. However, there lacks comprehensive studies that analyze the ambient drift (i.e., air-stability) and reliability of CNFETs. Here, for the first time, we thoroughly characterize and demonstrate how to overcome ambient drift and negative bias temperature instability (NBTI) in CNFETs using the following techniques: (1) Silicon Nitride encapsulation to limit ambient atmosphere induced threshold voltage shift (~8x reduction of median VT shift over 90 days) and (2) AC/pulsed operation to significantly improve CNFET NBTI vs. DC operation across a wide frequency range (e.g., 20% duty cycle AC operation at 10 MHz could extend CNFET NBTI time-to-failure by >10000x vs. DC for a target VT shift tolerance < 100 mV with gate stress bias VGS,stress = -1.2 V at 125 C).
{"title":"Overcoming Ambient Drift and Negative-Bias Temperature Instability in Foundry Carbon Nanotube Transistors","authors":"Andrew Yu, Tathagata Srimani, Max Shulaker","doi":"arxiv-2409.11297","DOIUrl":"https://doi.org/arxiv-2409.11297","url":null,"abstract":"Back-end-of-line (BEOL) logic integration is emerging as a complementary\u0000scaling path to supplement front-end-of-line (FEOL) Silicon. Among various\u0000options for BEOL logic, Carbon Nanotube Field-Effect Transistors (CNFETs) have\u0000been integrated within commercial silicon foundries, and complex CNFET circuits\u0000(e.g., RISC-V core, SRAM arrays) have been demonstrated. However, there lacks\u0000comprehensive studies that analyze the ambient drift (i.e., air-stability) and\u0000reliability of CNFETs. Here, for the first time, we thoroughly characterize and\u0000demonstrate how to overcome ambient drift and negative bias temperature\u0000instability (NBTI) in CNFETs using the following techniques: (1) Silicon\u0000Nitride encapsulation to limit ambient atmosphere induced threshold voltage\u0000shift (~8x reduction of median VT shift over 90 days) and (2) AC/pulsed\u0000operation to significantly improve CNFET NBTI vs. DC operation across a wide\u0000frequency range (e.g., 20% duty cycle AC operation at 10 MHz could extend CNFET\u0000NBTI time-to-failure by >10000x vs. DC for a target VT shift tolerance < 100 mV\u0000with gate stress bias VGS,stress = -1.2 V at 125 C).","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sound power levels or so-called source levels are essential quantities when it comes to evaluating the active space of bird species, both in the study of animal communication and when designing bioacoustic monitoring schemes. However, little data is available in the literature. In this paper I demonstrate the feasibility of the measurement of apparent sound power in the field for bird species by using a calibrated 4-microphone horizontal array deployed on the ground. Time differences of arrival allow for the location of the sound source. Assuming a point source, the apparent sound power level is estimated after correcting for ground reflection and spherical divergence but cannot be corrected for source directivity. The benefits of my approach that is inspired from engineering measurement standards for elevated sound sources, is to minimize the contribution from ground reflections and to allow for unattended measurements, or measurements when the bird is not visible, owing to either foliage or obscurity. Moreover, my paper brings new data on sound power for 4 species of birds.
{"title":"Unattended field measurement of bird source level","authors":"Guillaume Dutilleux","doi":"arxiv-2409.10957","DOIUrl":"https://doi.org/arxiv-2409.10957","url":null,"abstract":"Sound power levels or so-called source levels are essential quantities when\u0000it comes to evaluating the active space of bird species, both in the study of\u0000animal communication and when designing bioacoustic monitoring schemes.\u0000However, little data is available in the literature. In this paper I\u0000demonstrate the feasibility of the measurement of apparent sound power in the\u0000field for bird species by using a calibrated 4-microphone horizontal array\u0000deployed on the ground. Time differences of arrival allow for the location of\u0000the sound source. Assuming a point source, the apparent sound power level is\u0000estimated after correcting for ground reflection and spherical divergence but\u0000cannot be corrected for source directivity. The benefits of my approach that is\u0000inspired from engineering measurement standards for elevated sound sources, is\u0000to minimize the contribution from ground reflections and to allow for\u0000unattended measurements, or measurements when the bird is not visible, owing to\u0000either foliage or obscurity. Moreover, my paper brings new data on sound power\u0000for 4 species of birds.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259902","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wojciech Marciniak, Joanna Marciniak, José Ángel Castellanos-Reyes, Mirosław Werwiński
Uniaxially strained Fe--Co disordered alloys have emerged as promising candidates for cost-effective rare-earth-free permanent magnets due to their high magnetocrystalline anisotropy energy (MAE). Using first-principles, fully relativistic calculations within the coherent potential approximation and PBE exchange-correlation potential, we explore the MAE of tetragonal Fe--Co alloys under uniaxial compression. Our results reveal a previously uncharted high-MAE region, distinct from known structures and accessible through uniaxial compression.
单轴应变铁-钴无序合金因其高磁晶各向异性能(MAE)而成为具有成本效益的无稀土永磁体的理想候选材料。利用相干势近似和 PBE 交换相关势中的第一性原理、全相对论计算,我们探索了单轴压缩下四方铁-钴合金的 MAE。我们的结果揭示了一个以前未知的高 MAE 区域,它不同于已知的结构,并且可以通过单轴压缩进入。
{"title":"Giant magnetocrystalline anisotropy energy in Fe--Co alloy under uniaxial compression: first-principles prediction","authors":"Wojciech Marciniak, Joanna Marciniak, José Ángel Castellanos-Reyes, Mirosław Werwiński","doi":"arxiv-2409.11388","DOIUrl":"https://doi.org/arxiv-2409.11388","url":null,"abstract":"Uniaxially strained Fe--Co disordered alloys have emerged as promising\u0000candidates for cost-effective rare-earth-free permanent magnets due to their\u0000high magnetocrystalline anisotropy energy (MAE). Using first-principles, fully\u0000relativistic calculations within the coherent potential approximation and PBE\u0000exchange-correlation potential, we explore the MAE of tetragonal Fe--Co alloys\u0000under uniaxial compression. Our results reveal a previously uncharted high-MAE\u0000region, distinct from known structures and accessible through uniaxial\u0000compression.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"84 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alessandro Rossi, Ian Buchanan, Alberto Astolfo, Martyna Michalska, Daniel Briglin, Anton Charman, Daniel Josell, Sandro Olivo, Ioannis Papakonstantinou
X-ray phase contrast imaging (XPCI) provides higher sensitivity to contrast between low absorbing objects that can be invisible to conventional attenuation-based X-ray imaging. XPCI's main application has been so far focused on medical areas at relatively low energies (< 100 keV). The translation to higher energy for industrial applications, where energies above 150 keV are often needed, is hindered by the lack of masks/gratings with sufficiently thick gold septa. Fabricating such structures with apertures of tens of micrometers becomes difficult at depths greater than a few hundreds of micrometers due to aspect ratio dependent effects such as anisotropic etching, and preferential gold (Au) deposition at the top of the apertures. In this work, these difficulties are overcome by Deep Reactive Ion Etching optimized by a stepped parameters approach and bismuth-mediated superconformal filling of Au, ultimately resulting in 500 micrometers deep silicon masks filled with Au at bulk density. The obtained masks, tested in an Edge Illumination XPCI system with a conventional source and a photon-counting detector, show good agreement with simulations at different energy thresholds. They also demonstrate a higher phase sensitivity for highly absorbing objects when compared to lower aspect ratio masks, proving their potential for industrial non-destructive testing.
X 射线相位对比成像(XPCI)对低吸收物体之间的对比具有更高的灵敏度,而这些物体在传统的基于衰减的 X 射线成像中是看不到的。迄今为止,XPCI 的主要应用集中在能量相对较低(< 100 keV)的医疗领域。由于缺乏具有足够厚金隔板的掩膜/光栅,因此无法将其转化为更高能量的工业应用(通常需要 150 千伏以上的能量)。由于各向异性蚀刻和孔(Au)顶部优先金(Au)沉积等与长宽比相关的效应,在深度超过几百微米时,制造这种孔径为几十微米的结构变得十分困难。在这项工作中,通过阶梯参数优化的深度反应离子蚀刻法和铋介导的超共形金填充法克服了这些困难,最终得到了以大量密度填充金的 500 微米深硅掩模。在边缘照明 XPCI 系统中使用传统光源和光子计数探测器对所获得的掩膜进行了测试,结果显示在不同能量阈值下与模拟结果非常吻合。与较低纵横比的掩膜相比,它们对高吸收物体的相位灵敏度更高,这证明了它们在工业无损检测方面的潜力。
{"title":"Fabrication of Ultra-Thick Masks for X-ray Phase Contrast Imaging at Higher Energy","authors":"Alessandro Rossi, Ian Buchanan, Alberto Astolfo, Martyna Michalska, Daniel Briglin, Anton Charman, Daniel Josell, Sandro Olivo, Ioannis Papakonstantinou","doi":"arxiv-2409.11237","DOIUrl":"https://doi.org/arxiv-2409.11237","url":null,"abstract":"X-ray phase contrast imaging (XPCI) provides higher sensitivity to contrast\u0000between low absorbing objects that can be invisible to conventional\u0000attenuation-based X-ray imaging. XPCI's main application has been so far\u0000focused on medical areas at relatively low energies (< 100 keV). The\u0000translation to higher energy for industrial applications, where energies above\u0000150 keV are often needed, is hindered by the lack of masks/gratings with\u0000sufficiently thick gold septa. Fabricating such structures with apertures of\u0000tens of micrometers becomes difficult at depths greater than a few hundreds of\u0000micrometers due to aspect ratio dependent effects such as anisotropic etching,\u0000and preferential gold (Au) deposition at the top of the apertures. In this\u0000work, these difficulties are overcome by Deep Reactive Ion Etching optimized by\u0000a stepped parameters approach and bismuth-mediated superconformal filling of\u0000Au, ultimately resulting in 500 micrometers deep silicon masks filled with Au\u0000at bulk density. The obtained masks, tested in an Edge Illumination XPCI system\u0000with a conventional source and a photon-counting detector, show good agreement\u0000with simulations at different energy thresholds. They also demonstrate a higher\u0000phase sensitivity for highly absorbing objects when compared to lower aspect\u0000ratio masks, proving their potential for industrial non-destructive testing.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259954","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We experimentally and computationally analyze impact-shock-induced stress wave propagation in packings of disordered flexible fibers. We find that dispersive wave propagation, associated with large stress attenuation, occurs much more prevalently in systems with larger fiber aspect ratios and moderate fiber flexibility. We trace these features to the microstructural properties of fiber contact chains and the energy-trapping abilities of deformable fibers. These findings provide new insights into physics of the shock-impacted flexible fiber packings and open the way towards an improved granular-material-based damping technology.
{"title":"Dispersive wave propagation in disordered flexible fibers enhances stress attenuation","authors":"Peng Wang, Thomas Pähtz, Kun Luo, Yu Guo","doi":"arxiv-2409.10926","DOIUrl":"https://doi.org/arxiv-2409.10926","url":null,"abstract":"We experimentally and computationally analyze impact-shock-induced stress\u0000wave propagation in packings of disordered flexible fibers. We find that\u0000dispersive wave propagation, associated with large stress attenuation, occurs\u0000much more prevalently in systems with larger fiber aspect ratios and moderate\u0000fiber flexibility. We trace these features to the microstructural properties of\u0000fiber contact chains and the energy-trapping abilities of deformable fibers.\u0000These findings provide new insights into physics of the shock-impacted flexible\u0000fiber packings and open the way towards an improved granular-material-based\u0000damping technology.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"25 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
High resolution, hard x-ray spectroscopy at synchrotron x-ray light sources commonly uses spherically bent crystal analyzers (SBCAs) formed by shaping a single crystal wafer to a spherical backing. These Rowland circle optics are almost always used in a 'symmetric' (or nearly symmetric) configuration wherein the reciprocal lattice vector used for energy selectivity via diffraction is coincident with the normal vector to the curved wafer surface. However, Gironda, et al., recently proposed that asymmetric operation of SBCA, wherein the reciprocal lattice vector is no longer normal to the wafer surface, has significant operational benefits and has been an underutilized opportunity. First, those authors find improved energy resolution through decreased Johann error, or equivalently find increased solid angle at a chosen experimental tolerance for energy broadening. Second, they find productive, high-resolution use of a large number of reciprocal lattice vectors from a single SBCA, thus enabling operation over a wide energy range without need to exchange SBCA upon making large changes in desired photon energy. These observations hold the potential to improve performance, increase flexibility and decrease cost for both laboratory and synchrotron applications. Given these motivations, we report an open-source software package, hklhop, that enables exploration of the complex space of analyzer wafer choice, experimental energy range or ranges, and desired suppression of Johann error. This package can guide both the design and the day-to-day operations of Rowland spectrometers enabled for asymmetric use.
同步加速器 X 射线光源的高分辨率硬 X 射线光谱分析通常使用球形弯曲晶体分析器 (SBCAs),该分析器是通过将单个晶体晶片加工成球形背板而形成的。这些罗兰圆光学器件几乎总是在 "对称"(或近乎对称)配置中使用,在这种配置中,通过衍射进行能量选择的倒易晶格矢量与弯曲晶片表面的法向矢量重合。然而,Gironda 等人最近提出,SBCA 的非对称操作(即往复晶格矢量不再是晶圆表面的法线矢量)具有显著的操作优势,但这一机会一直未得到充分利用。首先,这些作者发现通过降低 Johannerror 提高了能量分辨率,或者说,在选定的能量展宽实验容限下增加了固角。其次,他们发现通过单个 SBCA 可以有效地、高分辨率地使用大量倒易晶格矢量,从而可以在很宽的能量范围内进行操作,而无需在所需光子能量发生较大变化时交换 SBCA。这些观察结果为提高实验室和同步加速器应用的性能、增加灵活性和降低成本提供了可能。有鉴于此,我们开发了一个开源软件包 hklhop,用于探索分析仪晶片选择、实验能量范围和所需的约翰误差抑制等复杂空间。该软件包可以指导不对称使用的罗兰光谱仪的设计和日常操作。
{"title":"hklhop: a Selection Tool for Asymmetric Reflections of Spherically Bent Crystal Analysers for High Resolution X-ray Spectroscopy","authors":"Jared E. Abramson, Yeu Chen, Gerald T. Seidler","doi":"arxiv-2409.10698","DOIUrl":"https://doi.org/arxiv-2409.10698","url":null,"abstract":"High resolution, hard x-ray spectroscopy at synchrotron x-ray light sources\u0000commonly uses spherically bent crystal analyzers (SBCAs) formed by shaping a\u0000single crystal wafer to a spherical backing. These Rowland circle optics are\u0000almost always used in a 'symmetric' (or nearly symmetric) configuration wherein\u0000the reciprocal lattice vector used for energy selectivity via diffraction is\u0000coincident with the normal vector to the curved wafer surface. However,\u0000Gironda, et al., recently proposed that asymmetric operation of SBCA, wherein\u0000the reciprocal lattice vector is no longer normal to the wafer surface, has\u0000significant operational benefits and has been an underutilized opportunity.\u0000First, those authors find improved energy resolution through decreased Johann\u0000error, or equivalently find increased solid angle at a chosen experimental\u0000tolerance for energy broadening. Second, they find productive, high-resolution\u0000use of a large number of reciprocal lattice vectors from a single SBCA, thus\u0000enabling operation over a wide energy range without need to exchange SBCA upon\u0000making large changes in desired photon energy. These observations hold the\u0000potential to improve performance, increase flexibility and decrease cost for\u0000both laboratory and synchrotron applications. Given these motivations, we\u0000report an open-source software package, hklhop, that enables exploration of the\u0000complex space of analyzer wafer choice, experimental energy range or ranges,\u0000and desired suppression of Johann error. This package can guide both the design\u0000and the day-to-day operations of Rowland spectrometers enabled for asymmetric\u0000use.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259953","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper proposes an efficient semi-analytical method using auxiliary sine series for transverse vibration and sound radiation of a thin rectangular plate with edges elastically restrained against translation and rotation. The formulation, constructed by two-dimensional sine and/or cosine series, can approximately express the bending displacement, and calculate vibration and sound radiation under excitation of point force, arbitrary-angle plane wave, or diffuse acoustic field with acceptable accuracy. It is also applied for baffled or unbaffled conditions. A post-process program is developed to predict vibrating frequencies and modes, mean square velocity spectrum, and sound transmission loss via reduced-order integrals of radiation impedances. The method is validated by experiment and simulation results, demonstrating accurate and efficient computation using a single program for transverse vibration and sound radiation of a plate under different elastic boundary conditions and different excitations. Formulas given in this paper provide a basis for the code development on transverse vibration and sound radiation analysis of thin plates.
{"title":"A semi-analytical method using auxiliary sine series for vibration and sound radiation of a rectangular plate with elastic edges","authors":"Guoming Deng, Xian Wu, Changxiao Shao, Songlin Zheng, Jianwang Shao","doi":"arxiv-2409.09929","DOIUrl":"https://doi.org/arxiv-2409.09929","url":null,"abstract":"This paper proposes an efficient semi-analytical method using auxiliary sine\u0000series for transverse vibration and sound radiation of a thin rectangular plate\u0000with edges elastically restrained against translation and rotation. The\u0000formulation, constructed by two-dimensional sine and/or cosine series, can\u0000approximately express the bending displacement, and calculate vibration and\u0000sound radiation under excitation of point force, arbitrary-angle plane wave, or\u0000diffuse acoustic field with acceptable accuracy. It is also applied for baffled\u0000or unbaffled conditions. A post-process program is developed to predict\u0000vibrating frequencies and modes, mean square velocity spectrum, and sound\u0000transmission loss via reduced-order integrals of radiation impedances. The\u0000method is validated by experiment and simulation results, demonstrating\u0000accurate and efficient computation using a single program for transverse\u0000vibration and sound radiation of a plate under different elastic boundary\u0000conditions and different excitations. Formulas given in this paper provide a\u0000basis for the code development on transverse vibration and sound radiation\u0000analysis of thin plates.","PeriodicalId":501083,"journal":{"name":"arXiv - PHYS - Applied Physics","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142259958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}