Article
Physics, Multidisciplinary
Gaokun Yu, Xinyu Zou, Peifeng Wang
Summary: An achromatic acoustic generalized phase-reversal zone plate is proposed by harnessing the response of dipole and monopole, which eliminates the chromatic aberration of conventional zone plates. The proposed metalens exhibits high efficient focusing properties in a frequency range from 3350 to 3950 Hz, with approximately twice the focal intensity of the conventional Soret-type Fresnel zone plate. The achromatic metalens has potential applications in acoustics, including imaging and energy harvesting.
NEW JOURNAL OF PHYSICS
(2022)
Article
Spectroscopy
Hung-Wei Shiu, Tzu-Hung Chuang, Cheng-Maw Cheng, Chia-Hao Chen, Yao-Jane Hsu, Der-Hsin Wei
Summary: Microscopy using soft X-ray as an illumination source can incorporate spectroscopy with images. Taiwan Light Source (TLS) implemented this capability with two photoelectron-based microscopy stations, using either zone-plate or electron lens. The project expanded to multiple stations and beamlines at Taiwan Photon Source (TPS) to take advantage of TPS's low emittance. This report summarizes the activities at TLS and introduces the status of microscopy stations under construction at TPS 27A and 39A.
JOURNAL OF ELECTRON SPECTROSCOPY AND RELATED PHENOMENA
(2023)
Article
Chemistry, Analytical
Hanna Ohlin, Thomas Frisk, Mattias Astrand, Ulrich Vogt
Summary: This study presents a miniaturized gold electroplating process for fabricating gold zone plates used in X-ray imaging experiments. The miniaturization is achieved by on-chip reference plating areas, providing a reliable way to control the height of the structures. The fabricated gold zone plates were successfully used in X-ray imaging experiments.
Article
Physics, Multidisciplinary
Jiecheng Yang, Peiping Zhu, Dong Liang, Hairong Zheng, Yongshuai Ge
Summary: A general theoretical framework is presented to explain the formation of the phase signal in an x-ray microscope integrated with a grating interferometer. This theory can predict key parameters of phase contrast imaging and has been validated through numerical simulations.
Article
Chemistry, Physical
Hirotoyo Nakashima, Arata Kinouchi, Masao Takeyama
Summary: Soft X-ray emission spectroscopy (SXES) technique combined with an electron probe micro analyzer was used to study the oxygen concentrations in the alpha-Ti and gamma-TiAl phases in the Ti-Al-O ternary system. The results showed that oxygen is enriched in the alpha phase and that the gamma phase can only dissolve a small amount of oxygen.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Physics, Applied
Yasushi Kagoshima, Yuki Takayama
Summary: The study numerically evaluated the OTF of an inverse-phase composite zone plate and found phase-reversed contrast at high spatial frequencies. Despite slight aberrations in the calculated OTF, its deep-focusing capability is advantageous for X-ray microimaging.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Y. A. Genenko, M. -H. Zhang, I. S. Vorotiahin, R. Khachaturyan, Y. -X. Liu, J. -W. Li, K. Wang, J. Koruza
Summary: This study proposes a stochastic model of electric-field-driven polarization reversal in orthorhombic ferroelectrics, which is validated in a lead-free orthorhombic ferroelectric ceramic. The analysis highlights the substantial contributions of coherent non-180 degrees switching events to the system.
Review
Biochemistry & Molecular Biology
Valentina Bonanni, Alessandra Gianoncelli
Summary: Scanning transmission X-ray microscopy (STXM) allows imaging of biological specimens and collection of localized spectroscopic information through X-ray fluorescence (XRF) and/or X-ray Absorption Near Edge Spectroscopy (XANES). Recent publications in synchrotrons have utilized soft X-ray spectro-microscopy in life science and environmental research to explore complex metabolic mechanisms by tracing chemical elements involved in metabolic pathways.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Nanoscience & Nanotechnology
Wei Zhou, Xiaodie Zhu, Jing Yu, Dedan Mou, Hongxing Li, Lingyu Kong, Tianchun Lang, Lingling Peng, Wenbo Chen, Xuhui Xu, Bitao Liu
Summary: In recent years, novel metal halide scintillators have shown great application potential due to their tunable emission wavelength, high X-ray absorption, and high luminescence efficiency. To address the issues of poor stability and complex device packaging, a multiprocessing strategy was introduced to prepare Cs3Cu2I5@PMMA scintillator films, resulting in high crystallinity, uniform size, excellent flexibility, high stable photoluminescence and radioluminescence performance, and high-resolution X-ray imaging capability. The prepared scintillator films can provide clear and accurate imaging recognition of objects with different complex structures, maintain stable X-ray imaging quality within 60 days, and achieve flexible X-ray imaging.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Physics, Multidisciplinary
Jakob Soltau, Markus Osterhoff, Tim Salditt
Summary: This novel approach to x-ray microscopy combines a multilayer zone plate with an iterative phase retrieval scheme to achieve high resolution and quantitative phase contrast.
PHYSICAL REVIEW LETTERS
(2022)
Article
Instruments & Instrumentation
M. Mazuritskiy, A. M. Lerer, A. Marcelli, S. B. Dabagov, M. Coreno, A. D'Elia, S. J. Rezvani
Summary: Synchrotron radiation sources were used to study the focusing properties and angular distribution of X-ray radiation at the exit of spherically bent microchannel plates (MCPs). Soft X-ray radiation at energies up to 1.5 keV can be effectively focused by MCPs with curvature radii of 30 mm and 50 mm, with a maximum focusing efficiency of up to 23%. The theoretical model for wave propagation through MCPs successfully explained the experimental results, confirming the wave channeling phenomenon in spherically bent MCPs.
JOURNAL OF SYNCHROTRON RADIATION
(2021)
Article
Chemistry, Multidisciplinary
Alessandra Gianoncelli, Valentina Bonanni, Gianluca Gariani, Francesco Guzzi, Lorella Pascolo, Roberto Borghes, Fulvio Bille, George Kourousias
Summary: Progress in nanotechnology requires high sensitivity and resolution material probing techniques, with soft X-ray microscopy being one of the most powerful tools in medicine and the life sciences for studying complex biological processes at micrometric and sub-micrometric length scales. The TwinMic soft X-ray microscopy end-station at the Elettra synchrotron demonstrates capabilities in medical and biological imaging, along with novel uses and developments.
APPLIED SCIENCES-BASEL
(2021)
Article
Materials Science, Multidisciplinary
Jianwei Zhao, Stephen D. Funni, Emily R. Molina, Elizabeth C. Dickey, Jacob L. Jones
Summary: Under the application of an external voltage, high electric field concentrations develop around the interdigitated electrode edges inside multilayer ceramic actuators (MLCAs). The local inhomogeneity in the electromechanical response is caused by the spatial distribution of the local electrical field. By utilizing synchrotron-based high-energy X-ray diffraction (XRD), the structural changes in partially electroded Nb-doped PbZrxTi1-xO3 samples as a function of applied electric field were investigated. The results show that the domain switching behavior and phase transitions are spatially dependent across the inactive regions in partially electroded samples, especially near the electrode edge and the tetragonal composition near the morphotropic phase boundary (MPB).
Article
Chemistry, Inorganic & Nuclear
Mei-Juan Xie, Wen-Fei Wang, Bao-Yi Li, Juan Gao, Yun-Fan Yan, Jian Lu, Fa-Kun Zheng, Guo-Cong Guo
Summary: Lead(II)-based coordination polymers (CPs) materials have attracted great interest in the field of radiation detection due to their strong X-ray attenuation and beneficial optoelectronic properties. In this work, a X-ray responsive scintillating 1D Pb(II)-CP material was synthesized by the self-assembly approach and showed competitive sensitivity and detection limit towards X-ray compared to classical scintillators PbWO4 (PWO), anthracene and some reported SMOFs.
INORGANIC CHEMISTRY COMMUNICATIONS
(2022)
Article
Nanoscience & Nanotechnology
Xujie Tong, Yifang Chen, Chengyang Mu, Qiucheng Chen, Xiangzhi Zhang, Guang Zeng, Yuchun Li, Zijian Xu, Jun Zhao, Xiangjun Zhen, Chengwen Mao, Hongliang Lu, Renzhong Tai
Summary: X-ray microscope, as an important nanoprobing tool, has a prevailing role in nano-inspections of materials. However, the efficiency of high-resolution zone plates is limited due to various factors. In this work, a compound Kinoform/Fresnel zone plate is proposed and demonstrated to achieve high resolution and high efficiency in soft x-ray. This is achieved by combining a dielectric Kinoform zone plate with a 15 nm resolution zone plate using greyscale electron beam lithography and atomic layer deposition.
Article
Physics, Fluids & Plasmas
Ki Hong Pae, Hoon Song, Chang-Mo Ryu, Chang Hee Nam, Chul Min Kim
PLASMA PHYSICS AND CONTROLLED FUSION
(2020)
Article
Physics, Multidisciplinary
Jae Hee Sung, Jin Woo Yoon, Il Woo Choi, Seong Ku Lee, Hwang Woon Lee, Jeong Moon Yang, Yeong Gyu Kim, Chang Hee Nam
JOURNAL OF THE KOREAN PHYSICAL SOCIETY
(2020)
Article
Instruments & Instrumentation
M. Ahsan Mahmood, Seong Geun Lee, Sang Hwa Lee, Ha-Na Kim, Kitae Lee, Izhar Ahmad, Jeong Moon Yang, Jin Woo Yoon, Hwang Woon Lee, Jae Hee Sung, Seong Ku Lee, Il Woo Choi, Chang Hee Nam
Summary: This study presents a proof of principle for onsite calibration of radiochromic film (EBT3) using CR-39 as an absolute proton-counting detector and laser-accelerated protons as a calibration source. The method involves a special detector assembly and dividing the proton beam into small beamlets to expose the EBT3 film with protons in a specific energy range. Calibration curves for EBT3 films were obtained in a low dose range and showed good agreement with traditional calibrations using conventional accelerators. The proposed method can be further extended for onsite calibration of radiochromic films of other types and for a higher range of dose values.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Optics
Jin Woo Yoon, Yeong Gyu Kim, Il Woo Choi, Jae Hee Sung, Hwang Woon Lee, Seong Ku Lee, Chang Hee Nam
Summary: This study demonstrates the achievement of ultra-high intensity laser using the CoReLS petawatt laser, with near diffraction-limited focusing obtained through wavefront correction and tight focusing. Statistical analysis of laser shots identified intensity fluctuation sources and verified the applicability of ultra-high intensity lasers in laser-matter interactions.
Article
Optics
Yeong Gyu Kim, Ji In Kim, Jin Woo Yoon, Jae Hee Sung, Seong Ku Lee, Change Hee Nam
Summary: The single-shot spatiotemporal characterization of an ultrahigh intensity laser pulse was conducted using a multispectral wavefront sensor, revealing a 15% reduction in focused laser intensity due to spatiotemporal distortion compared to diffraction-limited and transform-limited laser pulses.
Article
Physics, Multidisciplinary
Pengjie Wang, Zheng Gong, Seong Geun Lee, Yinren Shou, Yixing Geng, Cheonha Jeon, I. Jong Kim, Hwang Woon Lee, Jin Woo Yoon, Jae Hee Sung, Seong Ku Lee, Defeng Kong, Jianbo Liu, Zhusong Mei, Zhengxuan Cao, Zhuo Pan, Il Woo Choi, Xueqing Yan, Chang Hee Nam, Wenjun Ma
Summary: This study investigates the experimental results of generating highly energetic super-heavy ions using ultrathin targets and ultrashort laser pulses, demonstrating the importance of a novel self-calibrated diagnostic method for obtaining absolute energy spectra and charge-state distributions of ions. The results highlight the significance of laser intensity over pulse duration for ion acceleration, with the potential for increasing ion energy by utilizing composite targets for prolonged acceleration.
Article
Optics
Ji In Kim, Yeong Gyu Kim, Jeong Moon Yang, Jin Woo Yoon, Jae Hee Sung, Seong Ku Lee, Chang Hee Nam
Summary: In this study, we demonstrated the generation of sub-10 fs pulses through post-compression. By utilizing self-phase modulation and a spatial filter stage, the intensity modulation and intensity spikes induced by self-focusing were effectively reduced, resulting in a significant enhancement of the peak power.
Article
Physics, Multidisciplinary
Jong-Won Lee, Minju Kim, Gyeongbo Kang, Sam M. Vinko, Leejin Bae, Min Sang Cho, Hyun-Kyung Chung, Minseok Kim, Soonnam Kwon, Gyusang Lee, Chang Hee Nam, Sang Han Park, Jang Hyeob Sohn, Seong Hyeok Yang, Ulf Zastrau, Byoung Ick Cho
Summary: Ultrafast dynamics in photoexcited warm dense Cu were visualized using femtosecond x-ray absorption spectroscopy, revealing rich dynamical features related to d vacancies. Improved understanding can be achieved by including recombination dynamics of nonthermal electrons and changes in screening of the excited d block. The population balance between the 4sp and 3d bands is mainly determined by the recombination rate of nonthermal electrons, showing recovery of the underpopulated 3d block on picosecond timescales.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Fluids & Plasmas
Ki Hong Pae, Chul Min Kim, Vishwa Bandhu Pathak, Chang-Mo Ryu, Chang Hee Nam
Summary: A direct acceleration scheme using an intense few-cycle Laguerre-Gaussian (LG) laser pulse with controlled carrier-envelope phase (CEP) can stably generate high-energy electron beams. The CEP plays a key role in the electron injection and acceleration process.
PLASMA PHYSICS AND CONTROLLED FUSION
(2022)
Article
Physics, Multidisciplinary
Yang Hwan Kim, Hyeok Yun, Sung In Hwang, Igor A. Ivanov, Chang Hee Nam, Kyung Taec Kim
Summary: Coherent extreme ultraviolet (EUV) line emissions can be generated from an atom excited through frustrated tunneling ionization (FTI). The phase and intensity of the EUV emission are sensitive to the laser pulse and target position, as shown by angle-resolved EUV spectra. The four-step model for FTI emission accurately describes the coherent control of the EUV emission. These findings are crucial for developing high photon flux coherent EUV sources and utilizing the FTI emission in time-resolved spectroscopy.
NEW JOURNAL OF PHYSICS
(2022)
Article
Optics
Ji In Kim, Jin Woo Yoon, Jeong Moon Yang, Yeong Gyu Kim, Jae Hee Sung, Seong Ku Lee, Chang Hee Nam
Summary: We analyzed and corrected the wavefront distortion induced during the post-compression of a 100-TW Ti:Sapphire laser and achieved the intensity enhancement. By compensating for the wavefront aberrations with an adaptive optics system, the Strehl ratio of the post-compressed beam was improved and the focused intensity of the post-compressed beam could be enhanced.
Article
Instruments & Instrumentation
Do Yeon Kim, Calin Ioan Hojbota, Mohammad Mirzaie, Seong Ku Lee, Ki Yong Kim, Jae Hee Sung, Chang Hee Nam
Summary: Accurate spatiotemporal synchronization between ultrarelativistic electron bunch and ultrahigh-intensity laser beam is crucial in all-optical Compton scattering. This synchronization was achieved using two complementary optical setups, and the monitoring systems played an essential role in the experiments.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Physics, Multidisciplinary
Yang Hwan Kim, Igor A. Ivanov, Sung In Hwang, Kyungseung Kim, Chang Hee Nam, Kyung Taec Kim
Summary: An intense laser field can cause an electron to tunnel out and then be rescattered by the parent ion, leading to interesting physical phenomena. Recent research has shown that the measurement of the rescattered electron can provide real-time characterization of the laser field. In this study, we demonstrate that the measurement of the rescattering time of tunnel-ionized electrons can accurately resolve the rescattering times in Ar and Xe with an accuracy of a few attoseconds. This accurate measurement can provide deeper insights into ultrafast electron dynamics in an intense laser field.
JOURNAL OF THE KOREAN PHYSICAL SOCIETY
(2023)
Article
Physics, Multidisciplinary
Tae Gyu Pak, Yong Joo Rhee, Mohammad Mirzaie, Calin Ioan Hojbota, Jong Ho Jeon, Sung Ha Jo, Chang Hee Nam, Mohammad Rezaei-Pandari, Jae Hee Sung, Seong Ku Lee, Ki Yong Kim
Summary: We measured X-rays emitted perpendicular to the laser propagation direction in petawatt-laser-driven wakefield acceleration of electrons in a gas cell. Multi-mega-electronvolt electrons are ejected in the transverse direction, generating bremsstrahlung X-rays when they encounter a dense medium. The X-rays were detected and characterized by two separate filter-stack spectrometers, exhibiting peak energy fluences at around 150-200 keV. The mechanism of electron acceleration and subsequent bremsstrahlung X-ray generation was confirmed using simulations.
JOURNAL OF THE KOREAN PHYSICAL SOCIETY
(2023)
Article
Optics
L. J. Bae, G. B. Kang, M. Kim, G. S. Lee, J. H. Sohn, C. H. Nam, B. I. Cho
Summary: The temporal modulation of an electron bunch train accelerated from an intense laser pulse irradiated foil target is studied by measuring the coherent transition radiation (CTR) from the target's rear surface. Experimental CTR spectra were obtained from a 1 μm thick foil target irradiated at a maximum intensity of 6.5 x 1019 W/cm2, and spectral redshifts corresponding to increases in laser intensity were observed. These measurements were compared with theoretical calculations considering ultrafast surface dynamics, such as plasma surface oscillation and relativistically induced transparency.
