Article
Chemistry, Multidisciplinary
Christopher Perez, Atharv Jog, Heungdong Kwon, Daniel Gall, Mehdi Asheghi, Suhas Kumar, Woosung Park, Kenneth E. Goodson
Summary: In this study, time-domain thermoreflectance was used to uncover cross-plane heat conduction mechanisms in high aspect ratio metal nanostructures. The findings demonstrate the existence of unexplored heat transport modes in nanostructured metals, which can be utilized to develop electro-thermal solutions for modern microelectronic devices and sensors.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Materials Science, Ceramics
Xu Jiang, Jie Sun, Xiaojie Chai, Yifan Chen, Wei Zhang, Jun Jiang, Anquan Jiang
Summary: The study found that the wall current varies with the angle between the applied electric field and the initial polarization, and that the oxygen vacancy concentration can be controlled through thermal annealing, affecting the magnitude of the domain wall current.
CERAMICS INTERNATIONAL
(2021)
Article
Chemistry, Multidisciplinary
Yu-Hong Lai, Jun-Ding Zheng, Si-Cheng Lu, Yin-Kuo Wang, Chun-Gang Duan, Pu Yu, Yun-Zhe Zheng, Rong Huang, Li Chang, Ming-Wen Chu, Ju-Hung Hsu, Ying-Hao Chu
Summary: In condensed matter physics, oxide materials exhibit diverse and intriguing physical properties, making the development of functional oxides an important field of study. This research focuses on stabilizing PbSnO3 thin films with different orientations using a heteroepitaxial approach supported by theoretical calculations. Through X-ray diffraction and transmission electron microscopy, the structural information of the thin films is revealed. The electrical characterizations confirm the anticipated antiferroelectric behavior, including double hysteresis and butterfly loops. The study also investigates the phase transition and determines the transition temperatures based on temperature-dependent structural and electrical characterizations. Furthermore, scanning transmission electron microscopy provides atomic resolution images, revealing the microscopic antiferroelectric order. This work represents a significant breakthrough in synthesizing epitaxial PbSnO3 thin films and comprehensively understanding their anisotropic antiferroelectric behavior.
Review
Physics, Applied
Abhijit Biswas, William Joshua Kennedy, Nicholas R. R. Glavin, Pulickel M. M. Ajayan
Summary: In recent decades, there has been a significant increase in research focused on growing high quality atomically smooth epitaxial thin films, demonstrating unprecedented quantum correlated phenomena and a great potential for oxitronics. However, the growth of defect-free and highly conducting perovskite oxide thin films still remains an active area of research due to various factors influencing film quality and electronic properties. This review summarizes the progress in growing atomically smooth epitaxial thin films of highly conducting ABO(3) perovskites with low resistivity and highlights the importance of optimizing growth parameters and film-substrate interaction for achieving high-quality epitaxy. Highly conducting epitaxial oxide thin films are essential for bridging the gap between oxides and their practical integration in electronics.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Le Wang, Prajwal Adiga, Jiali Zhao, Widitha S. Samarakoon, Kelsey A. Stoerzinger, Steven R. Spurgeon, Bethany E. Matthews, Mark E. Bowden, Peter Sushko, Tiffany C. Kaspar, George E. Sterbinsky, Steve M. Heald, Han Wang, Linda W. Wangoh, Jinpeng Wu, Er-Jia Guo, Haijie Qian, Jiaou Wang, Tamas Varga, Suntharampillai Thevuthasan, Zhenxing Feng, Wanli Yang, Yingge Du, Scott A. Chambers
Summary: Fe substitution in LaNi1-xFexO3 tunes the Ni oxidation state, leading to a volcano-like OER trend with x = 0.375 as the most active. High-valent Fe3+δ cationic species enhance TM 3d bandwidth and TM 3d-O 2p hybridization, boosting the OER activity. These findings deepen our understanding of structural and electronic contributions to enhanced OER activity in perovskite oxides.
Article
Chemistry, Physical
Riccardo Magrin Maffei, Alessandro di Bona, Maria Sygletou, Francesco Bisio, Sergio D'Addato, Stefania Benedetti
Summary: In this study, we demonstrate that Al-doped ZnO (AZO) thin films grown epitaxially on SrTiO3 retain their optimal properties even at very small thicknesses. We investigate the film morphology, structure, crystallinity, electrical and optical properties. The results reveal that the epitaxial films exhibit high mobility due to ionized impurity scattering, while the polycrystalline films show deteriorated properties due to grain boundary scattering.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Physical
Bo Feng, Haiyuan Lv, Jie Liu, Rongrong Chen, Hongyan Zhu, Xinyu Han, Caina Luan, Hongdi Xiao
Summary: In this study, high-quality p-type CuInO2 epitaxial thin films were successfully grown on GaN wafers using pulsed laser deposition technology. The films exhibited a bandgap of around 3.99 eV. The quality of the CuInO2 thin film improved with decreasing oxygen pressure, and the highest quality film demonstrated high photoresponsivity and fast response speed in a solar-blind wavelength.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Zhongwen Li, Hui Shen, Graham Dawson, Zhengzhong Zhang, Yanzong Wang, Feng Nan, Guang Song, Guannan Li, Yangjiang Wu, Hao Liu
Summary: In this study, the authors used vector piezoresponse force microscopy to observe spontaneous ferroelectric topological domains in ferroelectric materials and discovered their topological arrangements and reversible switching characteristics. They also found that the domain diameter changes with pulse duration in different intrinsic domain structures and confirmed the stability of these topological domain states in the atmosphere.
JOURNAL OF MATERIALS CHEMISTRY C
(2022)
Article
Chemistry, Physical
Mythili Surendran, Huandong Chen, Boyang Zhao, Arashdeep S. Thind, Shantanu Singh, Thomas Orvis, Huan Zhao, Jae-Kyung Han, Han Htoon, Megumi Kawasaki, Rohan Mishra, Jayakanth Ravichandran
Summary: This study reports the direct epitaxial thin film growth of chalcogenide perovskite BaZrS3 by pulsed laser deposition, showing smooth film surfaces and strong potential for photovoltaic applications. The films exhibit clear epitaxial relationship with the substrate, and photodetector devices demonstrate fast and efficient photo response, making BaZrS3 a promising candidate for ultrathin front absorbers in tandem solar cells.
CHEMISTRY OF MATERIALS
(2021)
Article
Physics, Applied
Yogesh Sharma, Binod Paudel, Jegon Lee, Woo Seok Choi, Zhenzhong Yang, Han Wang, Yingge Du, Kyeong Tae Kang, Ghanshyam Pilania, Aiping Chen
Summary: This study investigates the effect of epitaxial strain on the magnetic and optical properties of perovskite LaCrO3 (LCO) single crystal thin films. By growing epitaxial LCO thin films with different strain states, a direct correlation between lattice-strain and functional properties is demonstrated. The results show that lattice anisotropy and strain-induced tetragonality in the film lattice play critical roles in controlling the magnetic behavior and optical transitions of LCO films.
APPLIED PHYSICS LETTERS
(2021)
Article
Multidisciplinary Sciences
Jijie Huang, Weijin Chen
Summary: This article summarizes the methods for fabricating high-quality flexible oxide thin films with novel functionalities and applications, and introduces various functionalities and applications of these films.
Article
Multidisciplinary Sciences
Shu Shi, Haolong Xi, Tengfei Cao, Weinan Lin, Zhongran Liu, Jiangzhen Niu, Da Lan, Chenghang Zhou, Jing Cao, Hanxin Su, Tieyang Zhao, Ping Yang, Yao Zhu, Xiaobing Yan, Evgeny Y. Tsymbal, He Tian, Jingsheng Chen
Summary: The authors demonstrate the stabilization of the metastable orthorhombic phase in Hf0.5 Zr0.5O2 films through interface engineering and hole doping.
NATURE COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
Xianlong Cheng, Chao Zhou, Baichen Lin, Zhenni Yang, Shanquan Chen, Kelvin H. L. Zhang, Zuhuang Chen
Summary: Fluorite-structured Hf0.5Zr0.5O2 (HZO) thin films have gained attention for their good CMOS-compatibility and robust ferroelectricity. However, the challenges of high leakage current and poor endurance hinder the application of HZO in microelectronic devices. This study investigates the electric properties of Pt/HZO/La0.7Sr0.3MnO3 (LSMO) heterostructures and finds that the leakage mechanism is dominated by Schottky emission. By post-annealing in oxygen atmosphere, the barrier height can be increased, effectively reducing leakage current and improving endurance.
APPLIED MATERIALS TODAY
(2023)
Article
Chemistry, Multidisciplinary
Yogesh Sharma, Binod Paudel, Amanda Huon, Matthew M. Schneider, Pinku Roy, Zachary Corey, Rico Schonemann, Andrew C. Jones, Marcelo Jaime, Dmitry A. Yarotski, Timothy Charlton, Michael R. Fitzsimmons, Quanxi Jia, Michael T. Pettes, Ping Yang, Aiping Chen
Summary: This study investigates the relationship between strain engineering, point defects, and ferromagnetism in actinide epitaxial thin films, and provides new insights into the influence of coupled order parameters on the emergent properties of actinide materials.
Article
Chemistry, Physical
Stephan Glamsch, Helmut Karl
Summary: Hydrogenated titanium dioxide (TiO2:H) thin films with thicknesses ranging from 33 to 300 nm were grown using reactive radio-frequency magnetron sputter deposition. The electrical resistivity, Seebeck coefficient, and optical absorption coefficient of these films were characterized. However, heating to temperatures above 430 K resulted in irreversible property changes, which depended on the atmosphere during thermal treatment.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Chemistry, Physical
Tsukasa Katayama, Shishin Mo, Akira Chikamatsu, Yuji Kurauchi, Hiroshi Kumigashira, Tetsuya Hasegawa
Summary: In this study, GdBaCo2O6 epitaxial films were successfully synthesized and reversible transformation between x = 5.5 and 6 phases was achieved via low-temperature redox reactions. The x = 6 film exhibited ferromagnetic and metallic behavior below 110 K and semiconducting behavior above. The ferromagnetic interaction between Co3.5+ and Gd3+ contributed to the magnetization and the half-metallicity of the film.
CHEMISTRY OF MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Meiqi Zhang, Fabien Grasset, Yuji Masubuchi, Toshihiro Shimada, Thi Kim Ngan Nguyen, Noee Dumait, Adele Renaud, Stephane Cordier, David Berthebaud, Jean-Francois Halet, Tetsuo Uchikoshi
Summary: The Mo cluster-MoS2 composite was synthesized through a one-step sulfurization process using H2/H2S gas flow. The decomposed Mo-6 cluster iodides acted as a template and precursor, forming complex Mo cluster compounds and eventually producing MoS2. After sulfurization, the response of the composite to NH3 gas increased three times while showing conversion from p-type to n-type semiconductor, enhancing its potential for device applications.
Article
Chemistry, Multidisciplinary
Ichiro Yamane, Kota Sato, Teruki Ando, Taijiro Tadokoro, Seiya Yokokura, Taro Nagahama, Yoshiki Kato, Tatsuya Takeguchi, Toshihiro Shimada
Summary: We investigated the pyrolysis process of copper-containing metal-organic frameworks under high pressure and demonstrated the influence of applied pressure on the morphology and electrocatalytic performance of the resulting products in oxygen-related reactions. High-pressure and high-temperature syntheses were conducted at different pressures, and Cu@C products were obtained except for the experiment at 2.5 GPa. The morphology of the copper incorporated into the carbon matrices varied with increasing pressure, suggesting the influence of copper transportation during pyrolysis. Electrochemical measurements revealed that all samples showed activity in the oxygen reduction reaction, with the product obtained at 0.5 GPa also exhibiting oxygen evolution reaction. Despite the absence of co-catalysts, the overall performance of the 0.5 GPa-treated product in ORR/OER was excellent among Cu-based bifunctional materials, attributed to the presence of Cu(iii) species in the nano-thick copper shell structure.
NANOSCALE ADVANCES
(2023)
Article
Physics, Applied
Tsukasa Katayama, Shishin Mo, Akira Chikamatsu, Tetsuya Hasegawa
Summary: Epitaxial M-type BaFe12O19 flexible sheets with RT perpendicular magnetization were successfully synthesized on mica substrates using solid phase epitaxy method. Optimization of the synthesis process involved preparation of amorphous BaFe12O19 films on Al2O3-buffered mica substrates and annealing at high temperatures for single crystallization. The prepared sheets exhibited perpendicular ferrimagnetism with high saturated magnetization and magnetic anisotropy coefficient, along with flexibility.
JAPANESE JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Shigeru Kobayashi, Kazunori Nishio, Markus Wilde, Katsuyuki Fukutani, Ryota Shimizu, Taro Hitosugi
Summary: The formation of an electrolyte-electrode interface that allows smooth Li-ion transport is crucial for the development of all-solid-state Li batteries. Water vapor is identified as a critical factor causing increased resistance at the interface, but the specific degradation mechanism remains unclear. This study investigates the contribution of protons to the degradation by introducing them to the LiCoO2 electrode through exposure to water vapor. Electrochemical, compositional, and structural analyses reveal that protons induce the mixing of Li and Co, leading to the formation of a low-temperature-phase LiCoO2 interphase layer that deteriorates battery performance. Understanding these interfacial phenomena enhances the power density of all-solid-state Li batteries.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Multidisciplinary Sciences
Kohei Fujiwara, Yasuyuki Kato, Hitoshi Abe, Shun Noguchi, Junichi Shiogai, Yasuhiro Niwa, Hiroshi Kumigashira, Yukitoshi Motome, Atsushi Tsukazaki
Summary: Amorphous semiconductors are widely used in electronic and energy-conversion devices. This study reveals that the short-range crystalline order in amorphous Fe-Sn films contributes to anomalous electrical and magneto-thermoelectric properties. This finding sheds light on the topology of amorphous materials and may enable the realization of functional topological amorphous electronic devices.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
M. Ohno, T. C. Fujita, Y. Masutake, H. Kumigashira, M. Kawasaki
Summary: Researchers have successfully synthesized two new metallic layered oxide compounds [BinOn+d]-[RhO2] (n = 2, 3) by pulsed laser deposition and subsequent annealing, and revealed dimensionality-dependent electrical transport behavior. This achievement paves the way for further exploration of novel layered oxide compounds.
Article
Chemistry, Physical
Ryoma Sasaki, Bo Gao, Taro Hitosugi, Yoshitaka Tateyama
Summary: Condensed matters with high ionic conductivities are essential in solid-state devices. However, computing correlated ionic conductivities is costly, leading to the use of approximations. This study presents a new method, CCD-NEMD, which allows for the calculation of correlated conductivities with fewer sampling steps. It is demonstrated to be effective in evaluating conductivities in solid electrolytes and can be applied to investigate grain boundaries and composite electrolytes.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Kazuki Nagai, Masato Anada, Kazuhiro Kowa, Miho Kitamura, Hiroshi Kumigashira, Hiroo Tajiri, Yusuke Wakabayashi
Summary: It has been found that oxide films thinner than a few unit cells are often insulating, and the Anderson localization supported by low dimensionality is one of the major mechanisms for this behavior. To distinguish the effects of randomness from dimensionality, the structural fluctuation and average structure of LaNiO3 thin films on LaAlO3 substrates were examined as a function of thickness. Surface x-ray diffraction experiment revealed little difference in average atomic position and atomic occupancy between 2 to 5 u.c. thick samples, with the main difference observed in the atomic displacement parameters. This suggests that structural fluctuation plays a role in interfacial transport properties, which is often neglected in discussions of oxide interface physics.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Inorganic & Nuclear
Ryuhei Oka, Keishi Ohara, Kensuke Konishi, Ichiro Yamane, Toshihiro Shimada, Toshio Naito
Summary: This study observed the interconversion process between DFs and SFs using organic charge-transfer salts. The low-symmetry crystals induced the reshaping of bands into Dirac cones with decreasing temperature, converting the behavior of SFs into that of DFs.
Article
Materials Science, Multidisciplinary
Tatsuhiko Kanda, Daisuke Shiga, Asato Wada, Ryotaro Hayasaka, Yuuki Masutake, Naoto Hasegawa, Miho Kitamura, Kohei Yoshimatsu, Hiroshi Kumigashira
Summary: Quantized states in strongly correlated oxide nanostructures are crucial for designing quantum devices in future electronics. In situ ARPES measurements in SrTi1-xVxO3 reveal that the electron mean free path is a key parameter for controlling and designing quantized states in these structures.
COMMUNICATIONS MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Hirohiko Tanoguchi, Takuma Yuki, Seiya Yokokura, Takashi Yanase, Mingoo Jin, Hajime Ito, Taro Nagahama, Toshihiro Shimada
Summary: Researchers have found a two-dimensional ambipolar material among cyclopenta-fused polycyclic aromatic hydrocarbon molecules and successfully revealed its crystal structure. The experimental investigation also confirmed ambipolar operation in a single-crystal FET and its potential for use in photoelectric conversion devices.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Proceedings Paper
Physics, Applied
Jun Sugiyama, Elisabetta Nocerino, Ola K. Forslund, Yasmine Sassa, Martin Mansson, Shigeru Kobayashi, Kazunori Nishio, Taro Hitosugi, Andreas Suter, Thomas Prokscha
Summary: In an all solid state Li-ion battery, reducing ionic resistivity at the electrode-electrolyte interface is essential for enhancing Li+ mobility. Recent calculations predict a space-charge layer (SCL) at the interface due to chemical potential differences, similar to electronic devices. However, the presence of SCL has never been experimentally observed. Our first attempt using low-energy mu+SR revealed a small change in field distribution width across the interface, suggesting the change at the SCL is too small to be detected.
15TH INTERNATIONAL CONFERENCE ON MUON SPIN ROTATION, RELAXATION AND RESONANCE
(2023)
Article
Materials Science, Multidisciplinary
Ryuhei Oka, Keishi Ohara, Naoya Tajima, Toshihiro Shimada, Toshio Naito
Summary: Materials containing Dirac fermions have unique electronic properties and have been extensively studied. In this study, it was found that a certain organic material contains nearly three-dimensional Dirac fermions coexistent with standard fermions. This finding was obtained through the analysis of electron spin resonance.
MATERIALS ADVANCES
(2023)
