Magnetic excitation in the =1/2 Ising-like antiferromagnetic chain CsCoCl in longitudinal magnetic fields studied by high-field ESR measurements

Kimura, Shojiro*; Onishi, Hiroaki; Okunishi, Koichi*; Akaki, Mitsuru*; Narumi, Yasuo*; Hagiwara, Masayuki*; Kindo, Koichi*; Kikuchi, Hikomitsu*

Journal of the Physical Society of Japan, 92(9), p.094701_1 - 094701_9, 2023/09

https://doi.org/10.7566/JPSJ.92.094701

Description of the inclusive reaction with the semiclassical distorted-wave model

Nakada, Hibiki*; Yoshida, Kazuki; Ogata, Kazuyuki*

Physical Review C, 108(3), p.034603_1 - 034603_8, 2023/09

https://doi.org/10.1103/PhysRevC.108.034603

The description of deuteron-induced inclusive reactions has been an important subject in direct nuclear reaction studies and nuclear data science. For proton-induced inclusive processes, the semiclassical distorted wave model (SCDW) is one of the most successful models based on quantum mechanics. We improve SCDW for deuteron-induced inclusive processes. The changes in the kinematics due to the distortion effect, the refraction effect, is taken into account by the local semiclassical approximation. The calculated cross section of reasonably reproduce experimental data in the small energy-transfer region and at forward and middle angles with some exceptions. The angular distributions of the cross section are improved by including the refraction effect. The effect on the cross section is significant compared to that on the proton-induced inclusive process because of the stronger distortion effect on the deuteron.

Observation of field-induced single-ion magnetic anisotropy in a multiorbital Kondo alloy (Lu,Yb)RhZn

Kitazawa, Takafumi; Ikeda, Yoichi*; Sakakibara, Toshiro*; Matsuo, Akira*; Shimizu, Yusei*; Tokunaga, Yo; Haga, Yoshinori; Kindo, Koichi*; Nambu, Yusuke*; Ikeuchi, Kazuhiko*; et al.

Physical Review B, 108(8), p.085105_1 - 085105_7, 2023/08

https://doi.org/10.1103/PhysRevB.108.085105

Level structures of Ca cast doubt on a doubly magic Ca

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

https://doi.org/10.1016/j.physletb.2023.138025

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.

Step unbunching phenomenon on 4H-SiC (0001) surface during hydrogen etching

Sakakibara, Ryotaro*; Bao, J.*; Yuhara, Keisuke*; Matsuda, Keita*; Terasawa, Tomoo; Kusunoki, Michiko*; Norimatsu, Wataru*

Applied Physics Letters, 123(3), p.031603_1 - 031603_4, 2023/07

https://doi.org/10.1063/5.0153565

We here report a step unbunching phenomenon, which is the inverse of the phenomenon of step bunching. When a 4H-SiC (0001) surface is annealed at a high temperature, step bunching arises due to the different velocities of the step motion in adjacent steps, resulting in steps with a height of more than several nanometers. We found that the bunched steps, thus, obtained by hydrogen etching in an Ar/H atmosphere were "unbunched" into lower height steps when annealed subsequently at lower temperatures. This unbunching phenomenon can be well explained by the consequence of the competition between energetics and kinetics. Our findings provide another approach for the surface smoothing of SiC by hydrogen etching and may give significant insight into the application of SiC power devices and two-dimensional materials growth techniques in general.

Magnetic hysteresis induction with nanocolumnar defects in magnetic insulators

Harii, Kazuya*; Umeda, Maki; Arisawa, Hiroki*; Hioki, Tomosato*; Sato, Nana; Okayasu, Satoru; Ieda, Junichi

Journal of the Physical Society of Japan, 92(7), p.073701_1 - 073701_4, 2023/07

https://doi.org/10.7566/JPSJ.92.073701

Emergence of inductance and capacitance from topological electromagnetism

Araki, Yasufumi; Ieda, Junichi

Journal of the Physical Society of Japan, 92(7), p.074705_1 - 074705_9, 2023/06

https://doi.org/10.7566/JPSJ.92.074705

Topological electromagnetism owing to nontrivial momentum-space topology of electrons in insulators gives rise to diverse anomalous magnetoelectric responses. While conventional inductors and capacitors are based on classical electromagnetism described by Maxwell's equations, here we show that topological electromagnetism in combination with spin dynamics in magnets also generates an inductance or a capacitance. We build a generic framework to extract the complex impedance on the basis of topological field theory, and demonstrate the emergence of an inductance or a capacitance in several heterostructure setups. In comparison with the previously-studied emergent inductances in metallic magnets, insulators highly suppress the power loss, because of the absence of Joule heating. We show that the inductance from topological electromagnetism is achieved at low current and high frequency, and is also advantageous in its power efficiency, as characterized by the high quality factor (Q-factor).

One fixed point can hide another one; Nonperturbative behavior of the tetracritical fixed point of O() models at large

Yabunaka, Shunsuke; Delamotte, B.*

Physical Review Letters, 130(26), p.261602_1 - 261602_6, 2023/06

https://doi.org/10.1103/PhysRevLett.130.261602

Low temperature behavior of itinerant ferromagnet realized in extended Nagaoka mechanism

Onishi, Hiroaki; Miyashita, Seiji*

JPS Conference Proceedings (Internet), 38, p.011157_1 - 011157_6, 2023/05

https://doi.org/10.7566/JPSCP.38.011157

Chiral superconductivity in UTe probed by anisotropic low-energy excitations

Ishihara, Kota*; Roppongi, Masaki*; Kobayashi, Masayuki*; Imamura, Kumpei*; Mizukami, Yuta*; Sakai, Hironori; Opletal, P.; Tokiwa, Yoshifumi; Haga, Yoshinori; Hashimoto, Kenichiro*; et al.

Nature Communications (Internet), 14, p.2966_1 - 2966_7, 2023/05

https://doi.org/10.1038/s41467-023-38688-y

The superconducting symmetry of the heavy fermion uranium-based superconductor UTe is investigated using low temperature penetration depth measurements. The anisotropic low-energy quasiparticle excitations indicates multiple superconducting components in a chiral complex form. The most consistent is a chiral non-unitary state.