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Your search keyword '"Chu, Yong S."' showing total 211 results
Start Over Author "Chu, Yong S." Publication Type Academic Journals
211 results on '"Chu, Yong S."'

17. A versatile high-speed x-ray microscope for sub-10 nm imaging.

Author

Xu, Weihe, Xu, Wei, Gao, Zirui, Gavrilov, Dmitri, Yan, Hanfei, Xu, Huijuan, Bouet, Nathalie, Zhou, Juan, Smith, Randy, Ma, Jun, Huang, Xiaojing, Chu, Yong S., and Nazaretski, Evgeny

Subjects
TOMOGRAPHY, SCANNING systems, ACQUISITION of data, OPTICS, MICROSCOPY
Abstract

We have developed a next-generation scanning x-ray microscope RASMI (RApid Scanning Microscopy Instrument) for high-throughput tomographic imaging. RASMI is installed at the hard x-ray nanoprobe beamline at NSLS-II and is capable of manipulating 1D multilayer Laue lenses (MLLs) and 2D optics (both zone plates and monolithically assembled 2D MLLs). The sample scanning stage utilizes line-focusing interferometry as an encoder while performing fly-scanning data acquisition. The system can be configured for both position- and time-triggering modes during fly-scanning. The microscope demonstrated a detector-limited data acquisition rate of 1.25 kHz during ptychography measurements. The initial x-ray results yielded a sample-limited resolution of ∼6 nm in 2D. RASMI can be adopted for in-vacuum applications and is a foundation for the next-generation scanning microscopy systems to be developed and commissioned at NSLS-II. [ABSTRACT FROM AUTHOR]

Published
2024
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18. Benchmarking of X‐Ray Fluorescence Microscopy with Ion Beam Implanted Samples Showing Detection Sensitivity of Hundreds of Atoms.

Author

Masteghin, Mateus G., Gervais, Toussaint, Clowes, Steven K., Cox, David C., Zelyk, Veronika, Pattammattel, Ajith, Chu, Yong S., Kolev, Nikola, Stock, Taylor J. Z., Curson, Neil J., Evans, Paul G., Stuckelberger, Michael, and Murdin, Benedict N.

Subjects
SEMICONDUCTOR doping, FIELD ion microscopy, ION beams, FLUORESCENCE microscopy, DOPING agents (Chemistry)
Abstract

Single impurities in insulators are now often used for quantum sensors and single photon sources, while nanoscale semiconductor doping features are being constructed for electrical contacts in quantum technology devices, implying that new methods for sensitive, non‐destructive imaging of single‐ or few‐atom structures are needed. X‐ray fluorescence (XRF) can provide nanoscale imaging with chemical specificity, and features comprising as few as 100 000 atoms have been detected without any need for specialized or destructive sample preparation. Presently, the ultimate limits of sensitivity of XRF are unknown – here, gallium dopants in silicon are investigated using a high brilliance, synchrotron source collimated to a small spot. It is demonstrated that with a single‐pixel integration time of 1 s, the sensitivity is sufficient to identify a single isolated feature of only 3000 Ga impurities (a mass of just 350 zg). With increased integration (25 s), 650 impurities can be detected. The results are quantified using a calibration sample consisting of precisely controlled numbers of implanted atoms in nanometer‐sized structures. The results show that such features can now be mapped quantitatively when calibration samples are used, and suggest that, in the near future, planned upgrades to XRF facilities might achieve single‐atom sensitivity. [ABSTRACT FROM AUTHOR]

Published
2024
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23. Mesoscale interplay among composition heterogeneity, lattice deformation, and redox stratification in single-crystalline layered oxide cathode.

Author

Zhichen Xue, Feixiang Wu, Mingyuan Ge, Xiaojing Huang, Chu, Yong S., Pianetta, Piero, and Yijin Liu

Subjects
LITHIUM-ion batteries, X-ray microscopy, FLUORESCENCE, ELECTROCHEMICAL analysis, CATHODES
Abstract

Single-crystalline layered oxide materials for lithium-ion batteries are featured by their excellent capacity retention over their polycrystalline counterparts, making them sought-after cathode candidates. Their capacity degradation, however, becomes more severe under high-voltage cycling, hindering many high-energy applications. It has long been speculated that the interplay among composition heterogeneity, lattice deformation, and redox stratification could be a driving force for the performance decay. The underlying mechanism, however, is not well-understood. In this study, we use X-ray microscopy to systematically examine single-crystalline NMC particles at the mesoscale. This technique allows us to capture detailed signals of diffraction, spectroscopy, and fluorescence, offering spatially resolved multimodal insights. Focusing on early high-voltage charging cycles, we uncover heterogeneities in valence states and lattice structures that are inherent rather than caused by electrochemical abuse. These heterogeneities are closely associated with compositional variations within individual particles. Our findings provide useful insights for refining material synthesis and processing for enhanced battery longevity and efficiency. [ABSTRACT FROM AUTHOR]

Published
2024
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26. Perovskite neural trees

Author

Zhang, Hai-Tian, Park, Tae Joon, Zaluzhnyy, Ivan A., Wang, Qi, Wadekar, Shakti Nagnath, Manna, Sukriti, Andrawis, Robert, Sprau, Peter O., Sun, Yifei, Zhang, Zhen, Huang, Chengzi, Zhou, Hua, Zhang, Zhan, Narayanan, Badri, Srinivasan, Gopalakrishnan, Hua, Nelson, Nazaretski, Evgeny, Huang, Xiaojing, Yan, Hanfei, Ge, Mingyuan, Chu, Yong S., Cherukara, Mathew J., Holt, Martin V., Krishnamurthy, Muthu, Shpyrko, Oleg G., Sankaranarayanan, Subramanian K.R.S., Frano, Alex, Roy, Kaushik, and Ramanathan, Shriram

Published
2020
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28. Manifold projection image segmentation for nano-XANES imaging.

Author

Tetef, Samantha, Pattammattel, Ajith, Chu, Yong S., Chan, Maria K. Y., and Seidler, Gerald T.

Subjects
MANIFOLDS (Engineering), IMAGE segmentation, MACHINE learning, SPATIAL resolution, SPECTRAL imaging
Abstract

As spectral imaging techniques are becoming more prominent in science, advanced image segmentation algorithms are required to identify appropriate domains in these images. We present a version of image segmentation called manifold projection image segmentation (MPIS) that is generally applicable to a broad range of systems without the need for training because MPIS uses unsupervised machine learning with a few physically motivated hyperparameters. We apply MPIS to nanoscale x-ray absorption near edge structure (XANES) imaging, where XANES spectra are collected with nanometer spatial resolution. We show the superiority of manifold projection over linear transformations, such as the commonly used principal component analysis (PCA). Moreover, MPIS maintains accuracy while reducing computation time and sensitivity to noise compared to the standard nano-XANES imaging analysis procedure. Finally, we demonstrate how multimodal information, such as x-ray fluorescence data and spatial location of pixels, can be incorporated into the MPIS framework. We propose that MPIS is adaptable for any spectral imaging technique, including scanning transmission x-ray microscopy, where the length scale of domains is larger than the resolution of the experiment. [ABSTRACT FROM AUTHOR]

Published
2023
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38. Achieving High-Resolution Hard X-ray Microscopy using Monolithic 2D Multilayer Laue Lenses.

Author

Xu, Wei, Xu, Weihe, Bouet, Nathalie, Zhou, Juan, Yan, Hanfei, Huang, Xiaojing, Lu, Ming, Zalalutdinov, Maxim, Chu, Yong S., and Nazaretski, Evgeny

Subjects
X-ray microscopy, HARD X-rays, FOCAL planes, FOCUS (Optics), FOCAL length, MAGNETRON sputtering, OPTICAL apertures
Abstract

B Fabrication of MLL optics. b The MLL optics were fabricated via magnetron sputtering deposition on a silicon substrate and further sectioned by reactive ion etching, followed by focused ion beam (FIB) milling. Discussion and Conclusion The developed monolithic MEMS-based 2D multilayer Laue lens nanofocusing optics significantly simplify the MLLs alignment process and, meanwhile, guarantee the angular and lateral alignment of assembled 2D optics. Keywords: X-ray microscopy; multilayer Laue lenses; optics; MEMS; microfabrication EN X-ray microscopy multilayer Laue lenses optics MEMS microfabrication 28 33 6 11/29/22 20221101 NES 221101 Introduction X-ray microscopy is a powerful characterization tool applied in many scientific fields, such as materials science, environmental science, biology, and energy research [[1]-[4]]. [Extracted from the article]

Published
2022
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43. Production and performance of multilayer-coated conical x-ray mirrors

Author

Ulmer, Melville P., Altkorn, Robert, Graham, Michael E., Madan, Anita, and Chu, Yong S.

Subjects
Optics -- Research, Astronomy, Physics
Abstract

A method of fabricating replica figured x-ray optics with integral multilayer coatings is presented. With the intact electroforming multilayer process (IEMP) technique, we sputter multilayers onto a reusable superpolished mandrel, electroform nickel over the multilayers, and remove the multilayer-coated nickel shell intact from the mandrel. This approach offers advantages over more traditional, original, and segmented-replica fabrication techniques, including low cost; compatibility with a wide range of mirror designs, diameters, and focal lengths; simple integration with multilayer sputtering processes; and the ability to produce complete shells of revolution. The fabrication of W/Si multilayer-coated 10-cm-diameter conical x-ray mirrors is described, as are reflectivity measurements at 10 and 30 keV. The measured reflectivity of the IEMP multilayers at the 10-keV primary Bragg peak was 17%. Measurements of multiple points on the cone showed multilayer uniformity to within a few percent around the mirror. OCIS codes: 340.7470, 340.6720, 310.1860, 350.1260.

Published
2003

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