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Yoneda, Yasuhiro; Kobayashi, Toru; Tsuji, Takuya; Matsumura, Daiju; Saito, Yuji; Noguchi, Yuji*
Japanese Journal of Applied Physics, 63(9), p.09SP12_1 - 09SP12_10, 2024/09
Times Cited Count:0 Percentile:0.00(Physics, Applied)NaNbO, AgNbO
, and KNbO
with ABO
-type perovskite system is known to possess good ferroelectric properties. We directly determined the rattling space of each atom through local structure analysis. This analysis revealed the bonding sites with large fluctuations varied with varying ion size. Experimental evidence including soft X-ray absorption spectroscopy, indicates that the A-site ions are hybridized with oxygen.
Katsumata, Tetsuhiro*; Suzuki, Ryo*; Sato, Naoto*; Oda, Ryoya*; Motoyama, Shingo*; Suzuki, Shumpei*; Nakashima, Mamoru*; Inaguma, Yoshiyuki*; Mori, Daisuke*; Aimi, Akihisa*; et al.
Chemistry of Materials, 36(8), p.3697 - 3704, 2024/04
Times Cited Count:0 Percentile:0.00(Chemistry, Physical)A perovskite-type oxynitride BaFeOF was prepared by high-pressure synthesis. Since the SHG signal was observed in the obtained material, suggesting the existence of spontaneous polarization, the mechanism of polarization was investigated by synchrotron high-energy X-ray diffraction. The obtained pair distribution functions were fitted, and a local polarization mechanism with different orientations was found. Since BaFeO
F is also a magnetic material, a magnetic domain and a ferroelectric domain are considered to coexist.
Linh, B. D.*; Corsi, A.*; Gillibert, A.*; Obertelli, A.*; Doornenbal, P.*; Barbieri, C.*; Duguet, T.*; Gmez-Ramos, M.*; Holt, J. D.*; Hu, B. S.*; et al.
Physical Review C, 109(3), p.034312_1 - 034312_15, 2024/03
Times Cited Count:1 Percentile:68.69(Physics, Nuclear)no abstracts in English
Yoneda, Yasuhiro; Kobayashi, Toru; Tsuji, Takuya; Matsumura, Daiju; Saito, Yuji; Noguchi, Yuji*
Japanese Journal of Applied Physics, 62(SM), p.SM1006_1 - SM1006_8, 2023/11
Times Cited Count:4 Percentile:54.88(Physics, Applied)BiNa
TiO
BaTiO
(BNT
BT) solid solutions have been extensively studied because they exhibit good piezoelectric properties. In addition, a wide variety of phases are observed depending on the BT composition. Soft X-ray absorption spectroscopy and high-energy X-ray diffraction experiments of BNT
BT solid solutions were performed using synchrotron radiation. From the electronic structure and local structure of BNT
BT solid solution, the substitution effect of BT occurred mainly at the A site, which is the substitution site of Ba. The rhombohedral strain of the TiO
octahedron did not change with the change in BT composition, suggesting that the change in the electronic structure at the O-
absorption edge is due to the change in the hybridization state.
Kondo, Yosuke*; Achouri, N. L.*; Al Falou, H.*; Atar, L.*; Aumann, T.*; Baba, Hidetada*; Boretzky, K.*; Caesar, C.*; Calvet, D.*; Chae, H.*; et al.
Nature, 620(7976), p.965 - 970, 2023/08
Times Cited Count:23 Percentile:94.90(Multidisciplinary Sciences)no abstracts in English
Yoneda, Yasuhiro; Tsuji, Takuya; Matsumura, Daiju; Okamoto, Yoshihiro; Takaki, Seiya; Takano, Masahide
Physica B; Condensed Matter, 663, p.414960_1 - 414960_9, 2023/08
Times Cited Count:0 Percentile:0.00(Physics, Condensed Matter)We performed various synchrotron X-ray measurements to extract local and average structures of DyN-ZrN solid solutions. We performed the nanoscale structural analysis by combining X-ray absorption fine structure and high-energy X-ray diffraction. The DyN-ZrN solid solution has a rock-salt type cubic crystal structure, and there are instabilities such as the chemical order of the metal site and the distribution of the bond length of the nitrogen site.
Wang, H.*; Yasuda, Masahiro*; Kondo, Yosuke*; Nakamura, Takashi*; Tostevin, J. A.*; Ogata, Kazuyuki*; Otsuka, Takaharu*; Poves, A.*; Shimizu, Noritaka*; Yoshida, Kazuki; et al.
Physics Letters B, 843, p.138038_1 - 138038_9, 2023/08
Times Cited Count:3 Percentile:64.77(Astronomy & Astrophysics)Detailed -ray spectroscopy of the exotic neon isotope
Ne has been performed using the one-neutron removal reaction from
Ne. Based on an analysis of parallel momentum distributions, a level scheme with spin-parity assignments has been constructed for
Ne and the negative-parity states are identified for the first time. The measured partial cross sections and momentum distributions reveal a significant intruder p-wave strength providing evidence of the breakdown of the N = 20 and N = 28 shell gaps. Only a weak, possible f-wave strength was observed to bound final states. Large-scale shell-model calculations with different effective interactions do not reproduce the large p-wave and small f-wave strength observed experimentally, indicating an ongoing challenge for a complete theoretical description of the transition into the island of inversion along the Ne isotopic chain.
Chen, S.*; Browne, F.*; Doornenbal, P.*; Lee, J.*; Obertelli, A.*; Tsunoda, Yusuke*; Otsuka, Takaharu*; Chazono, Yoshiki*; Hagen, G.*; Holt, J. D.*; et al.
Physics Letters B, 843, p.138025_1 - 138025_7, 2023/08
Times Cited Count:6 Percentile:84.52(Astronomy & Astrophysics)Gamma decays were observed in Ca and
Ca following quasi-free one-proton knockout reactions from
Sc. For
Ca, a
ray transition was measured to be 1456(12) keV, while for
Ca an indication for a transition was observed at 1115(34) keV. Both transitions were tentatively assigned as the
decays. A shell-model calculation in a wide model space with a marginally modified effective nucleon-nucleon interaction depicts excellent agreement with experiment for
level energies, two-neutron separation energies, and reaction cross sections, corroborating the formation of a new nuclear shell above the N = 34 shell. Its constituents, the
and
orbitals, are almost degenerate. This degeneracy precludes the possibility for a doubly magic
Ca and potentially drives the dripline of Ca isotopes to
Ca or even beyond.
Pohl, T.*; Sun, Y. L.*; Obertelli, A.*; Lee, J.*; Gmez-Ramos, M.*; Ogata, Kazuyuki*; Yoshida, Kazuki; Cai, B. S.*; Yuan, C. X.*; Brown, B. A.*; et al.
Physical Review Letters, 130(17), p.172501_1 - 172501_8, 2023/04
Times Cited Count:11 Percentile:88.84(Physics, Multidisciplinary)We report on the first proton-induced single proton- and neutron-removal reactions from the neutron deficient O nucleus with large Fermi-surface asymmetry at
100 MeV/nucleon. Our results provide the first quantitative contributions of multiple reaction mechanisms including the quasifree knockout, inelastic scattering, and nucleon transfer processes. It is shown that the inelastic scattering and nucleon transfer, usually neglected at such energy regime, contribute about 50% and 30% to the loosely bound proton and deeply bound neutron removal, respectively.
Yoneda, Yasuhiro
JSAP Review (Internet), 2023, p.230202_1 - 230202_7, 2023/00
It is important to determine whether a sample is a single phase or not in order to improve the quality of ferroelectrics. Therefore, we have succeeded in developing a detection method for trace amounts of segregated phases by using two-body correlation distribution function (PDF) in addition to X-ray diffraction, which has been conventionally used to detect impurities. In the X-ray diffraction pattern of the BaTiO-BiFeO
solid solution, it appears as a single phase with a rhombohedral structure. However, when the PDF was calculated from the obtained diffraction pattern, it was found that not only the component derived from the rhombohedral crystal structure calculated from the average structure but also the BaTiO
component was mixed and segregated. By using PDF in this way, it has become possible to detect fine segregation phases on the order of nanoscale.
Yoneda, Yasuhiro
Oyo Butsuri, 91(12), p.729 - 735, 2022/12
It is important to determine whether a sample is a single phase or not in order to improve the quality of ferroelectrics. Therefore, we have succeeded in developing a detection method for trace amounts of segregated phases by using two-body correlation distribution function (PDF) in addition to X-ray diffraction, which has been conventionally used to detect impurities. In the X-ray diffraction pattern of the BaTiO-BiFeO
solid solution, it appears as a single phase with a rhombohedral structure. However, when the PDF was calculated from the obtained diffraction pattern, it was found that not only the component derived from the rhombohedral crystal structure calculated from the average structure but also the BaTiO
component was mixed and segregated. By using PDF in this way, it has become possible to detect fine segregation phases on the order of nanoscale.
Elekes, Z.*; Juhsz, M. M.*; Sohler, D.*; Sieja, K.*; Yoshida, Kazuki; Ogata, Kazuyuki*; Doornenbal, P.*; Obertelli, A.*; Achouri, N. L.*; Baba, Hidetada*; et al.
Physical Review C, 106(6), p.064321_1 - 064321_10, 2022/12
Times Cited Count:2 Percentile:34.70(Physics, Nuclear)The low-lying level structure of V and
V was investigated for the first time. The neutron knockout reaction and inelastic proton scattering were applied for
V while the neutron knock-out reaction provided the data for
V. Four and five new transitions were determined for
V and
V, respectively. Based on the comparison to our shell-model calculations using the Lenzi-Nowacki-Poves-Sieja (LNPS) interaction, three of the observed
rays for each isotope could be placed in the level scheme and assigned to the decay of the first 11/2
and 9/2
levels. The (
,
) excitation cross sections for
V were analyzed by the coupled-channels formalism assuming quadrupole plus hexadecapole deformations. Due to the role of the hexadecapole deformation,
V could not be unambiguously placed on the island of inversion.
Enciu, M.*; Liu, H. N.*; Obertelli, A.*; Doornenbal, P.*; Nowacki, F.*; Ogata, Kazuyuki*; Poves, A.*; Yoshida, Kazuki; Achouri, N. L.*; Baba, Hidetada*; et al.
Physical Review Letters, 129(26), p.262501_1 - 262501_7, 2022/12
Times Cited Count:14 Percentile:84.80(Physics, Multidisciplinary)The one-neutron knockout from Ca was performed at
230 MeV/nucleon combined with prompt
spectroscopy. The momentum distributions corresponding to the removal of
and
neutrons were measured. The cross sections are consistent with a shell closure at the neutron number
, found as strong as at
and
in Ca isotopes from the same observables. The analysis of the momentum distributions leads to a difference of the root-mean-square radii of the neutron
and
orbitals of 0.61(23) fm, in agreement with the modified-shell-model prediction of 0.7 fm suggesting that the large root-mean-square radius of the
orbital in neutron-rich Ca isotopes is responsible for the unexpected linear increase of the charge radius with the neutron number.
Yoneda, Yasuhiro; Kim, S.*; Mori, Shigeo*; Wada, Satoshi*
Japanese Journal of Applied Physics, 61(SN), p.SN1022_1 - SN1022_10, 2022/11
Times Cited Count:3 Percentile:27.65(Physics, Applied)Local structural analysis of the (1-) BiFeO
-
BaTiO
solid solution was performed by PDF analysis of the data obtained in the synchrotron radiation high-energy X-ray diffraction experiment. First, when XAFS experiments were performed and sample screening was performed, it was found that structural fluctuations were large in the BiFeO
-rich composition. Therefore, PDF analysis of a sample with BiFeO
-rich composition was performed. As a result, it was found that although the average structure is a cubic structure, the local structure can be reproduced with a rhombohedral crystal structure, and there is a displacement that breaks the symmetry of the rhombohedral structure in a composition with a large fluctuation.
Kyono, Atsushi*; Yamamoto, Genichiro*; Yoneda, Yasuhiro; Okada, Satoru*
Isotope News, (783), p.23 - 27, 2022/10
Mineral traps are attracting attention as an underground storage method for carbon dioxide. Carbon dioxide laden groundwater reacts with basalt to form magnesite. The formed magnesium carbonate phase varies in many ways, but we tried to clarify the structure because all of them pass through amorphous magnesium carbonate. Pair distribution function using high-energy X-ray diffraction revealed that amorphous magnesium carbonate has a structure similar to that of hydromagnesite. It can be said that it is a safe sequestration method as a carbon dioxide storage technology.
Yagi, Yutaro*; Wakita, Yudai*; Kagomiya, Isao*; Matsue, Ikuya*; Kakimoto, Kenichi*; Matsumura, Daiju; Yoneda, Yasuhiro
ChemistrySelect (Internet), 7(21), p.e202104575_1 - e202104575_7, 2022/06
Times Cited Count:0 Percentile:0.00(Chemistry, Multidisciplinary)Koiwai, Takuma*; Wimmer, K.*; Doornenbal, P.*; Obertelli, A.*; Barbieri, C.*; Duguet, T.*; Holt, J. D.*; Miyagi, Takayuki*; Navrtil, P.*; Ogata, Kazuyuki*; et al.
Physics Letters B, 827, p.136953_1 - 136953_7, 2022/04
Times Cited Count:6 Percentile:75.27(Astronomy & Astrophysics)no abstracts in English
Nakashima, Koichi*; Hironaka, Kota*; Ouchi, Kazuma*; Ajioka, Mao*; Kobayashi, Yoshio*; Yoneda, Yasuhiro; Yin, S.*; Kakihana, Masato*; Sekino, Toru*
ACS Omega (Internet), 6(48), p.32517 - 32527, 2021/12
Times Cited Count:7 Percentile:37.29(Chemistry, Multidisciplinary)The BaTiO nanoparticles synthesized by the hydrothermal method is examined by synchrotron X-ray and TEM observation. It was found that the particle size of synthesized BaTiO
depends on the particle size of the raw material of TiO
. Succeeded in synthesizing 100 nm size BaTiO
nanocrystals showing uniform particle size distribution using TiO
nanoparticles with optimized particle size. The obtained BaTiO
nanocrystal is a tetragonal system of ferroelectric phase. A three-dimensional structure of BaTiO
nanoparticles could be obtained by the electron beam tomography.
Yoneda, Yasuhiro; Noguchi, Yuji*
Japanese Journal of Applied Physics, 60(SF), p.SFFA08_1 - SFFA08_10, 2021/11
Times Cited Count:5 Percentile:25.58(Physics, Applied)BiNa
TiO
(abbreviated as BNT) is a lead-free material but exhibits relatively large piezoelectric properties, a lot of researches have been conducted. We performed local structural analysis using high-quality BNT with a stoichiometrically correct composition, and found a chemical order structure of Bi/Na in locally. BNT undergoes a phase transition to a cubic phase at 400
C. We estimated that a new disorder structure will appear in the high-temperature phase. In the high temperature phase, pair distribution function (PDF) analysis using synchrotron radiation high-energy X-rays was performed. As a result, we found that Bi shifts from 200
C, and this shift becomes an order parameter for the phase transition.
Linh, B. D.*; Corsi, A.*; Gillibert, A.*; Obertelli, A.*; Doornenbal, P.*; Barbieri, C.*; Chen, S.*; Chung, L. X.*; Duguet, T.*; Gmez-Ramos, M.*; et al.
Physical Review C, 104(4), p.044331_1 - 044331_16, 2021/10
Times Cited Count:9 Percentile:73.68(Physics, Nuclear)no abstracts in English