Article
Physics, Multidisciplinary
Zi-Tao Zhang, Yu-Jie Qiao, Ting-Na Shao, Qiang Zhao, Xing-Yu Chen, Mei-Hui Chen, Fang-Hui Zhu, Rui-Fen Dou, Hai-Wen Liu, Chang-Min Xiong, Jia-Cai Nie
Summary: The origin of the quantum superconductor-to-metal transition is still unknown in two-dimensional superconductors, leading to intense discussion. In this study, we observed a quantum superconductor-to-metal transition in the LaAlO3/KTaO3 (111) interface driven by a magnetic field. The residual saturated resistance indicates the emergence of an anomalous metallic state associated with a failed superconductor. Our findings suggest that the magnetic field regulating the LaAlO3/KTaO3 (111) interface provides a controllable platform to investigate the details of the anomalous metallic state.
CHINESE PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Hai L. Feng, Chang-Jong Kang, Pascal Manuel, Fabio Orlandi, Yu Su, Jie Chen, Yoshihiro Tsujimoto, Joke Hadermann, Gabriel Kotliar, Kazunari Yamaura, Emma E. McCabe, Martha Greenblatt
Summary: Pb2NiOsO6 is a metallic and antiferromagnetic oxide that shows a single transition at low temperatures, with three-dimensional connectivity. Neutron powder diffraction and first-principles calculation studies indicate that both Ni and Os moments are ordered below the transition temperature, breaking inversion symmetry. This unusual loss of inversion symmetry in metallic systems makes the 3d-Sd double-perovskite oxides a new class of noncentrosymmetric antiferromagnetic metallic oxides.
CHEMISTRY OF MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Ying Xing, Pu Yang, Jun Ge, Jiaojie Yan, Jiawei Luo, Haoran Ji, Zeyan Yang, Yongjie Li, Zijia Wang, Yanzhao Liu, Feng Yang, Ping Qiu, Chuanying Xi, Mingliang Tian, Yi Liu, Xi Lin, Jian Wang
Summary: This study observed the intrinsic anomalous metallic state in 2D superconductors by filtering out external radiation, revealing a quantum ground state at ultralow temperatures. Additionally, Ising superconductivity was detected in 4H-TaSe2, suggesting weak coupling between TaSe2 submonolayers.
Article
Chemistry, Multidisciplinary
Qiao Jin, Hu Cheng, Zhiwen Wang, Qinghua Zhang, Shan Lin, Manuel A. Roldan, Jiali Zhao, Jia-Ou Wang, Shuang Chen, Meng He, Chen Ge, Can Wang, Hui-Bin Lu, Haizhong Guo, Lin Gu, Xin Tong, Tao Zhu, Shanmin Wang, Hongxin Yang, Kui-juan Jin, Er-Jia Guo
Summary: The study reveals that by controlling the film thickness of highly crystalline CrN films, a significant reduction in electrical conductivity accompanied by unexpected volume expansion can be observed. When the film thickness reaches approximately 30 unit cells, the conductivity of CrN films is greatly reduced.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Ahmad Bagheri, Sebastiano Bellani, Hossein Beydaghi, Matilde Eredia, Leyla Najafi, Gabriele Bianca, Marilena Isabella Zappia, Milad Safarpour, Maedeh Najafi, Elisa Mantero, Zdenek Sofer, Guorong Hou, Vittorio Pellegrini, Xinliang Feng, Francesco Bonaccorso
Summary: Efficient and durable flexible solid-state supercapacitors are essential for portable and wearable electronics. This study proposes an innovative composite solid-state electrolyte by incorporating metallic two-dimensional group-5 transition metal dichalcogenides into a sulfonated poly(ether ether ketone) polymeric matrix. The resulting solid-state electrolyte exhibits high proton conductivity and mechanical stability, making it ideal for use in solid-state supercapacitors.
Article
Physics, Condensed Matter
Kenta Hashimoto, Suguru Kitani, Hitoshi Kawaji
Summary: We investigated the thermal transport properties of Cu1-xZnxIr2S4 (0 < x < 0.3) and found an abrupt change in thermal conductivity during the metal-insulator transition. This is attributed to a significant decrease in the phonon thermal conductivity and mean free path, indicating the introduction of anomalous phonon scattering in the metallic phase.
PHYSICA B-CONDENSED MATTER
(2022)
Article
Physics, Multidisciplinary
Arvind Shankar Kumar, Chieh-Wen Liu, Shuhao Liu, Xuan P. A. Gao, Alex Levchenko, Loren N. Pfeiffer, Kenneth W. West
Summary: We report an unusual magnetoresistance in a dilute two-dimensional hole system in GaAs/AlGaAs quantum wells, where the magnetoresistance strengthens with increasing temperature even at the Fermi energy. This positive magnetoresistance at high temperatures is attributed to the viscous transport of the 2D hole fluid in the hydrodynamic regime. These findings provide insights into the collective transport of strongly interacting carriers and offer new possibilities for high-temperature magnetoresistance.
PHYSICAL REVIEW LETTERS
(2023)
Article
Chemistry, Physical
Ravi Ranjan, Nitin B. Mhamane, Sadhu K. Kolekar, Chinnakonda S. Gopinath
Summary: Gas-solid interactions and evolution of electronic structure of vanadium oxide surfaces were studied using near-ambient pressure photo-electron spectroscopy. It was found that vanadium oxidation is thermodynamically controlled, with metallic vanadium disappearing above a certain temperature and predominantly being oxidized to VO2. The coexistence of VOx and VO2 results in a metallic nature of VO2, with only partial surface conversion to V2O5. Different oxide properties can be observed through changes in work function and Fermi level features.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Multidisciplinary Sciences
Minguk Jo, Ye-Won Seo, Hyojin Yoon, Yeon-Seo Nam, Si-Young Choi, Byung Joon Choi, Junwoo Son
Summary: Embedded metallic nanoparticles enhance the metastability and memory effects of metallic domains in VO2 switches. Control of percolative dynamics of metal and insulator domains during electrically triggered insulator-metal transition underlies applications in energy-efficient switches and non-Boolean computing.
NATURE COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Sergei Ivanov, Joshua Peacock, Sergei Urazhdin
Summary: We propose a two-orbital Hubbard model for explaining electron correlations in ultrathin (111)-oriented fcc films of late transition metals. Our findings show that the Mott-Hund's interaction leads to ferromagnetic nearest-neighbor orbital correlations. However, due to frustration caused by the mismatch between orbital and crystal symmetries, orbital ordering is inhibited, resulting in the orbital liquid state. This state can be observed in phenomena related to spin-orbit coupling, such as magnetic anisotropy.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Physical
Minu Kim, Graham M. McNally, Hun-Ho Kim, Mohamed Oudah, Alexandra S. Gibbs, Pascal Manuel, Robert J. Green, Ronny Sutarto, Tomohiro Takayama, Alexander Yaresko, Ulrich Wedig, Masahiko Isobe, Reinhard K. Kremer, D. A. Bonn, Bernhard Keimer, Hidenori Takagi
Summary: Superconductivity is observed in (Ba,K)SbO3, stabilized by high-pressure synthesis, with a positive oxygen-metal charge transfer energy. This discovery suggests that strong oxygen-metal covalency might be more important than the sign of the charge transfer energy in the origin of superconductivity in main-group perovskite superconductors.
Article
Materials Science, Multidisciplinary
Yujie Wang, Chenchen Lou, Bao Zhao, Chunlan Ma, Jiayong Zhang
Summary: In this study, the electronic, magnetic, and topological properties of monolayer NiAl2S4 were investigated using first-principles calculations. Monolayer NiAl2S4 was found to be in a noncollinear 1200-antiferromagnetic state and have an indirect band gap, making it a promising candidate for spintronics devices. Hole doping can effectively tune the magnetic structure of monolayer NiAl2S4, resulting in a high Curie temperature half-metallic state. Additionally, the inclusion of spin-orbit coupling leads to the opening of topologically nontrivial gaps with Chern numbers of 1 around the non-Dirac I' point and Dirac K/K' points.
Article
Materials Science, Multidisciplinary
Takuhiro Ogino, Ryui Kaneko, Satoshi Morita, Shunsuke Furukawa, Naoki Kawashima
Summary: The study investigates a quantum phase transition between a Neel phase and a valence bond solid (VBS) phase in a spin-1/2 two-leg XXZ ladder with a four-spin interaction. The Neel-VBS transition is found to be continuous and belong to the Gaussian universality class, with critical exponents satisfying expected constraints. These critical exponents do not significantly change along the phase boundary as generally allowed for the Gaussian class.
Article
Chemistry, Physical
Zhengjing Zhao, Donglai Li, Junlin Yang, Jingbo Li, Haibo Jin
Summary: In this work, Nb-doped VO2 films were prepared by hydrothermal process, and the effects of Nb dopants on the metal-insulator transition (MIT) behavior were investigated. It was found that the valence variation of Nb dopants can modify the band structure of VO2, and Nb5+ dopants promote the MIT transition at a higher rate compared to Nb4+ dopants. Moreover, the Nb doping does not significantly affect the optical properties of VO2, indicating its promising applications in smart window and other optical switching devices.
APPLIED SURFACE SCIENCE
(2023)
Article
Multidisciplinary Sciences
Kyuho Lee, Bai Yang Wang, Motoki Osada, Berit H. Goodge, Tiffany C. C. Wang, Yonghun Lee, Shannon Harvey, Woo Jin Kim, Yijun Yu, Chaitanya Murthy, Srinivas Raghu, Lena F. Kourkoutis, Harold Y. Hwang
Summary: The occurrence of superconductivity in proximity to strongly correlated phases of matter has sparked interest in understanding the normal state properties that give rise to superconductivity. The recent discovery of superconductivity in layered nickelates has generated similar interest. However, transport measurements of doped infinite-layer nickelate thin films have been limited by material constraints, including a high density of extended defects. By using a substrate that better stabilizes the growth and reduction conditions, we were able to synthesize doped Nd1-xSrxNiO2 films essentially free from extended defects. This allowed us to observe similar normal state resistivity behaviors to the copper oxides, despite key distinctions in their electronic structure and insulating properties.
Article
Chemistry, Inorganic & Nuclear
Xin Zheng, Masaru Kato, Yohei Uemura, Daiju Matsumura, Ichizo Yagi, Kiyonori Takahashi, Shin-ichiro Noro, Takayoshi Nakamura
Summary: A glass-crystal composite (g-NCP/PCP) was synthesized using a melt-quenched method, consisting of a glassy nonporous coordination polymer (g-NCP) and a crystalline porous coordination polymer (PCP)/metal-organic framework. The g-NCP/PCP showed improved gas adsorption selectivity compared to the PCP alone. These results should encourage further research on the chemistry of g-NCP/PCP glass-crystal composites.
INORGANIC CHEMISTRY
(2023)
Article
Physics, Multidisciplinary
Takumi Mitsuoka, Yu Takahashi, Takeshi Suzuki, Mario Okawa, Hidenori Takagi, Naoyuki Katayama, Hiroshi Sawa, Minoru Nohara, Mari Watanabe, Jiadi Xu, Qianhui Ren, Masami Fujisawa, Teruto Kanai, Jiro Itatani, Kozo Okazaki, Shik Shin, Takashi Mizokawa
Summary: The photoinduced semimetal phase of Ta2Ni1-xCoxSe5 (x = 0.0 and 0.1) was studied using time-resolved angle-resolved photoemission spectroscopy. The observed band dispersions roughly agree with the generalized gradient approximation (GGA) calculation, but fail to reproduce the band gap at ambient conditions. This suggests that the electron-hole interaction, not properly included in GGA, is screened out by the photoexcited carriers. No indication of pseudogap was found. The conduction and valence bands exhibit quasi one-dimensional Fermi surfaces with similar momentum positions, indicating a quasi one-dimensional line-node semimetal.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Nanoscience & Nanotechnology
Baocai Du, Kenjiro Fukuda, Tomoyuki Yokota, Daishi Inoue, Daisuke Hashizume, Sixing Xiong, Shinyoung Lee, Masahito Takakuwa, Lulu Sun, Jiachen Wang, Takao Someya
Summary: Insufficient interfacial adhesion is a common problem in multilayered devices, causing reliability issues. In flexible organic photovoltaics (OPVs), poor adhesion between layers can lead to degradation and failure under mechanical deformations. By using argon plasma treatment, we were able to increase the interfacial adhesion between the active layer and the MoOX hole transport layer by 58%, improving mechanical reliability. The treated active layer had a higher surface energy, contributing to the improved adhesion. The mechanically stabilized interface prolonged the lifespan of the flexible OPV device under mechanical stress.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Kohei Inagawa, Daiju Matsumura, Masashi Taniguchi, Shinya Uegaki, Tomohito Nakayama, Junnosuke Urano, Takuro Aotani, Hirohisa Tanaka
Summary: Passive autocatalytic recombiner (PAR) is a potential technology for ensuring process safety in the hydrogen society by catalytically oxidizing hydrogen to water, effectively mitigating the risk of explosions. CO is a catalyst poison that hampers catalytic reactions. In situ and time-resolved X-ray absorption spectroscopy analyses revealed that the Pt-Fe/CZY catalyst exhibited notable hydrogen oxidation activity even in the presence of CO, attributed to the combined effects of Pt-Fe alloy composition and CZY support materials.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Physics, Multidisciplinary
Yu Takahashi, Takeshi Suzuki, Masaki Hattori, Mario Okawa, Hidenori Takagi, Naoyuki Katayama, Hiroshi Sawa, Minoru Nohara, Yigui Zhong, Kecheng Liu, Teruto Kanai, Jiro Itatani, Shik Shin, Kozo Okazaki, Takashi Mizokawa
Summary: In this study, the temporal evolution and fluence dependence of band structure in Ta2Ni0.9Co0.1Se5 were investigated using tr-ARPES. The results show the formation of a photoinduced semimetal phase and a partial gap/pseudogap, indicating the vital role of lattice fluctuations in the residual pseudogap after photoexcitation.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Materials Science, Multidisciplinary
Ryota Kasugai, Yoshifumi Kadowaki, Yasunori Yokoyama, Naoyuki Katayama, Yoshihiko Okamoto, Koshi Takenaka
Summary: This systematic investigation examines the specific effects of co-doping onto Zn sites in Mg-doped Zn2P2O7, shedding light on negative thermal expansion (NTE). The low-cost and low-environmental-impact NTE material Zn2_xMgxP2O7 exhibits significant NTE at x=0.4 in a temperature range that includes room temperature. Although Mg doping expands the operating-temperature window, it remains several dozen degrees wide. Additionally, the total volume change related to NTE decreases compared to the Zn2P2O7 parent material. Co-doping of Mg and another element onto the Zn site effectively achieves simultaneous expansion of the operating-temperature window and maintenance of the volume change related to NTE, as demonstrated by the example of Zn1.64Mg0.30Al0.06P2O7. This material exhibits a large negative coefficient of linear thermal expansion of approximately -65 ppm/K at temperatures of 300-375 K and shows better thermal expansion compensation capability than the composition without Al at temperatures higher than room temperature. The Al-doped phosphates are expected to have broad practical applications due to their performance, cost, and environmental load characteristics.
MATERIALS TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Daigorou Hirai, Naoto Uematsu, Koh Saitoh, Naoyuki Katayama, Koshi Takenaka
Summary: New high-entropy antimonides, M1-x Pt x Sb (M = equimolar Ru, Rh, Pd, and Ir), were successfully synthesized through a conventional solid-state reaction and subsequent quenching. Physical property measurements of single-phase M1-x Pt x Sb (x = 0.2) samples revealed a bulk superconducting transition at 2.15(2) K.
INORGANIC CHEMISTRY
(2023)
Article
Physics, Condensed Matter
Daigorou Hirai, Takahito Anbai, Takako Konoike, Shinya Uji, Yuya Hattori, Taichi Terashima, Hajime Ishikawa, Koichi Kindo, Naoyuki Katayama, Tamio Oguchi, Zenji Hiroi
Summary: Quantum oscillations were measured in the magnetic torque and electrical resistivity of ss-ReO2 to examine its electronic structure. The observed de Haas-van Alphen oscillation branches were consistent with first-principles calculations that predicted the presence of four Fermi surfaces. The small-electron Fermi surface exhibited a very small cyclotron mass, only 0.059 times that of free electrons, which suggests a linear dispersion of the energy band. These findings support the existence of the predicted hourglass nodal chain in ss-ReO2 near the Fermi energy.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Physics, Multidisciplinary
Koki Eto, Yoshihiko Okamoto, Naoyuki Katayama, Hajime Ishikawa, Koichi Kindo, Koshi Takenaka
Summary: NaPrTe2, NaNdTe2, and NaTbTe2 are triangular lattice magnets with the alpha-NaFeO2 structure, where lanthanoid atoms with 4f electrons form a triangular lattice. The alpha-NaFeO2 structure is a new polymorph of NaPrTe2, which was previously thought to have a cubic LiTiO2 structure. NaPrTe2 is suggested to be of interest for dimensional control of geometrically frustrated lattices. Magnetic susceptibility and heat capacity data show that NaPrTe2 does not exhibit long-range magnetic order or spin-glass transition above 2 K.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2023)
Article
Materials Science, Multidisciplinary
Raito Nakamura, Azumi Ishita, Jin Nakamura, Hiroto Ohta, Yuya Haraguchi, Hiroko Aruga Katori, Hajime Ishikawa, Akira Matsuo, Koichi Kindo, Minoru Nohara, Akihiko Ikeda
Summary: The 122 compounds of the Eu(Co1-xNix)2P2 solid solution exhibit a valence transition between divalent and intermediate valence states at Eu, which is related to structural transition, magnetism and formation of P-P dimers. The effect of high magnetic fields on the Eu valence-fluctuating regime samples is investigated, revealing that magnetostriction and magnetization increase smoothly with the magnetic fields. The results indicate that the Eu valence changes manifest themselves in magnetization curves at high magnetic fields.
Article
Materials Science, Multidisciplinary
H. Okamura, T. Mizokawa, K. Miki, Y. Matsui, N. Noguchi, N. Katayama, H. Sawa, M. Nohara, Y. Lu, H. Takagi, Y. Ikemoto, T. Moriwaki
Summary: The effect of pressure on the electronic state of Ta2NiSe5 has been studied. It was found that the energy gap becomes narrower and the excitonic peak diminishes with increasing pressure. After a structural transition, Ta2NiSe5 becomes a semimetal. This phenomenon is mainly attributed to the weakening of excitonic correlation with pressure.
Article
Chemistry, Multidisciplinary
Ryoto Yura, Shohei Kumagai, Kiyohiro Adachi, Daisuke Hashizume, Toshihiro Okamoto, Yoshiyuki Nonoguchi
Summary: This study demonstrates that supramolecular salt-functionalized n-doped ladder-type conducting polymers exhibit excellent stability in the presence of dry air.
CHEMICAL COMMUNICATIONS
(2023)
Article
Materials Science, Multidisciplinary
K. Kojima, N. Kattayama, Y. Matsuda, M. Shiomi, R. Ishii, H. Sawa
Summary: Vanadium atoms in layered LiVO2 form in-plane periodic vanadium trimers at low temperatures, but the trimers appear randomly in the stacking direction due to the presence of various similar energetically favorable trimer configurations. Our original modeling scheme represents glassy states with completely disordered trimer configurations in the stacking structure. Using pair distribution function analysis, we demonstrate that the synthesis method yields two types of low-temperature stacking structures: completely disordered and short-range ordered. The former sample has a phase-transition temperature about 15 K lower than the latter, attributed to the strong trimer frustration in the sample without short-range order, similar to the frustration effect in conventional spin systems.
