Spin density wave and van Hove singularity in the kagome metal CeTiBi

Park, P.*; Ortiz, B. R.*; Spargue, M.*; Sakuya, A. P.*; Chen, S. A.*; Frontzek, M. D.*; Tian, W.*; Sibille, R.*; Mazzone, D. G.*; Tabata, Chihiro; et al.

Nature Communications (Internet), 16, p.4384_1 - 4384_9, 2025/05

https://doi.org/10.1038/s41467-025-59460-4

Magnetic excitation in the hyperkagome antiferromagnet MnRhSi

Shamoto, Shinichi; Yamauchi, Hiroki; Iida, Kazuki*; Ikeuchi, Kazuhiko*; Kaneko, Koji; Chen, Y.-S.*; Yano, Shinichiro*; Hsu, P.-T.*; Lee, M. K.*; Hall, A. E.*; et al.

Physical Review Research (Internet), 6(3), p.033303_1 - 033303_7, 2024/09

https://doi.org/10.1103/PhysRevResearch.6.033303

The magnetic excitation extends at least from 0.3 to 140 meV. The integrated inelastic scattering intensity leads to a localized magnetic moment of about 5 per Mn site fluctuating at 200 K in the wide energy range, although the long-range ordered magnetic moment is only 2.61 at 4 K. The result suggests that a large part of the magnetic moment does not order in MnRhSi.

Giant barocaloric effects in sodium hexafluorophosphate and hexafluoroarsenate

Zhang, Z.*; Hattori, Takanori; Song, R.*; Yu, D.*; Mole, R.*; Chen, J.*; He, L.*; Zhang, Z.*; Li, B.*

Journal of Applied Physics, 136(3), p.035105_1 - 035105_8, 2024/07

https://doi.org/10.1063/5.0211085

Solid-state refrigeration using barocaloric materials is environmentally friendly and highly efficient, making it a subject of global interest over the past decade. Here, we report giant barocaloric effects in sodium hexafluorophosphate (NaPF) and sodium hexafluoroarsenate (NaAsF) that both undergo a cubic-to-rhombohedral phase transition near room temperature. We have determined that the low-temperature phase structure of NaPF is a rhombohedral structure with space group R and NaAsF, i.e., F, E, and A. The phase transition temperature varies with pressure at a rate of dT/dP = 250 and 310 K/GPa for NaPF and NaAsF. The pressure-induced entropy changes of NaPF and NaAsF are determined to be around 45.2 and 35.6J kgK, respectively. The saturation driving pressure is about 40 MPa. The pressure-dependent neutron powder diffraction suggests that the barocaloric effects are related to the pressure-induced cubic-to-rhombohedral phase transitions.

System of radiological protection; Towards a consistent framework on earth and in space

Rhm, W.*; Ban, Nobuhiko*; Chen, J.*; Li, C.*; Dobynde, M.*; Durante, M.*; El-Jaby, S.*; Komiyama, Tatsuto*; Ozasa, Kotaro*; Sato, Tatsuhiko; et al.

Journal of Medical Physics - Zeitschrift fr medizinische Physik -, 34(1), p.4 - 13, 2024/02

https://doi.org/10.1016/j.zemedi.2024.01.004

The International Commission on Radiological Protection (ICRP) provides independent recommendations on radiological protection for the public benefit. For more than 90 years, the ICRP System of Radiological Protection has been guiding the development and implementation of national and international standards and regulations on radiological protection. In 2019, ICRP established Task Group (TG) 115 to address a broader range of topics related to dose and risk assessment for radiological protection of astronauts. This paper gives an overview of the System of Radiological Protection and a brief summary of ICRP's work on radiological protection of astronauts.

Strongly coupled spin waves and surface acoustic waves at room temperature

Hwang, Y.*; Puebla, J.*; Kondo, Kota*; Gonzalez-Ballestero, C.*; Isshiki, Hironari*; Snchez Muoz, C.*; Liao, L.*; Chen, F.*; Luo, W.*; Maekawa, Sadamichi*; et al.

Physical Review Letters, 132(5), p.056704_1 - 056704_7, 2024/01

https://doi.org/10.1103/PhysRevLett.132.056704

Spiral spin cluster in the hyperkagome antiferromagnet MnRhSi

Shamoto, Shinichi; Yamauchi, Hiroki; Iida, Kazuki*; Ikeuchi, Kazuhiko*; Hall, A. E.*; Chen, Y.-S.*; Lee, M. K.*; Balakrishnan, G.*; Chang, L.-J.*

Communications Physics (Internet), 6, p.248_1 - 248_6, 2023/09

https://doi.org/10.1038/s42005-023-01363-1

We show that the local spin correlation order has a spiral structure by neutron scattering measurement of a MnRhSi single crystal. The possible origins of the magnetic cluster formation are discussed in terms of the Lifshitz invariant and the Griffiths phase, and compared with the room-temperature skyrmion phase of CoZnMn and non-Fermi liquid behavior of -Mn.

NIBS 2020 reference sheets

Sarmento, T.*; Wnderlich, D.*; Fantz, U.*; Friedl, R.*; Rauner, D.*; Tsumori, Katsuyoshi*; Shenjin, L.*; Chen, W.*; Bollinger, D.*; Oguri, Hidetomo; et al.

AIP Conference Proceedings 2373, p.110001_1 - 110001_18, 2021/08

https://doi.org/10.1063/5.0057732

In preparation for NIBS 2020 various labs prepared reference sheets containing key information about their ion sources and the machines that they serve. The contents of the reference sheets have been formatted and edited into this paper for posterity and ease of access.

Nagasaki sediments reveal that long-term fate of plutonium is controlled by select organic matter moieties

Lin, P.*; Xu, C.*; Kaplan, D. I.*; Chen, H.*; Yeager, C. M.*; Xing, W.*; Sun, L.*; Schwehr, K. A.*; Yamazaki, Hideo*; Kokubu, Yoko; et al.

Science of the Total Environment, 678, p.409 - 418, 2019/08

https://doi.org/10.1016/j.scitotenv.2019.04.375

Nagasaki sediments containing bomb-derived Pu provided a unique opportunity to explore the long term geochemical behavior of Pu. Through a combination of selective extractions and molecular characterization via electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry, we determined that 55 3% of the Pu was preferentially associated with more persistent organic matter compounds in Nagasaki sediments, particularly those natural organic matter (NOM) stabilized by Fe oxides. Other organic matter compounds served as a secondary sink of these Pu (31 2% on average), and less than 20% of the Pu was immobilized by inorganic mineral particles. While present long-term disposal and environmental remediation modeling assume that solubility limits and sorption to mineral surfaces control Pu subsurface mobility, our observations suggest that NOM undoubtedly plays an important role in sequestering Pu. Ignoring the role of NOM in controlling Pu fate and transport is not justified in most environmental systems.

Atomically dispersed Pt on the surface of Ni particles; Synthesis and catalytic function in hydrogen generation from aqueous ammonia-borane

Li, Z.*; He, T.*; Matsumura, Daiju; Miao, S.*; Wu, A.*; Liu, L.*; Wu, G.*; Chen, P.*

ACS Catalysis, 7(10), p.6762 - 6769, 2017/10

https://doi.org/10.1021/acscatal.7b01790

Characterization of the n_TOF EAR-2 neutron beam

Chen, Y. H.*; Tassan-Got, L.*; Harada, Hideo; Kimura, Atsushi; n_TOF Collaboration*; 130 of others*

EPJ Web of Conferences, 146, p.03020_1 - 03020_4, 2017/09

https://doi.org/10.1051/epjconf/201714603020

The experimental area 2 (EAR-2) at CERNs neutron time-of-flight facility (n_TOF), which is operational since 2014, is designed and built as a short-distance complement to the experimental area 1 (EAR-1). The Parallel Plate Avalanche Counter (PPAC) monitor experiment was performed to characterize the beam profile and the shape of the neutron flux at EAR-2. The prompt -flash which is used for calibrating the time-of-flight at EAR-1 is not seen by PPAC at EAR-2, shedding light on the physical origin of this -flash.