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Hybridized propagation of spin waves and surface acoustic waves in a multiferroic-ferromagnetic heterostructure

Chen, J.*; 山本 慧; Zhang, J.*; Ma, J.*; Wang, H.*; Sun, Y.*; Chen, M.*; Ma, J.*; Liu, S.*; Gao, P.*; et al.

Physical Review Applied (Internet), 19(2), p.024046_1 - 024046_9, 2023/02

Coherent coupling in magnon based hybrid system has many potential applications in quantum information processing. Magnons can propagate in magnetically ordered materials without any motion of electrons, offering a unique method to build low-power-consumption devices and information channels free of heat dissipation. In this article, we demonstrate the coherent propagation of hybridized modes between spin waves and Love surface acoustic waves in a multiferroic BiFeO$$_{3}$$ and ferromagnetic La$$_{0.67}$$Sr$$_{0.33}$$MnO$$_{3}$$ based heterostructure. The magneto-elastic coupling enables a giant enhancement of strength of the hybridized mode by a factor of 26 compared to that of the pure spin waves. A short wavelength down to 250 nm is demonstrated for the hybridized mode, which is desirable for nanoscale acousto-magnonic applications. Our combined experimental and theoretical analyses represent an important step towards the coherent control in hybrid magnonics, which may inspire the study of magnon-phonon hybrid systems for coherent information processing and manipulation.


$$S$$-wave fully charmed tetraquark resonant states

Wang, G.-J.*; Meng, Q.*; 岡 眞

Physical Review D, 106(9), p.096005_1 - 096005_9, 2022/11

クォーク模型を用いて、チャームクォークの4体系であるテトラクォークのS波の共鳴状態の探索を行った。複素スケーリング法を用いた計算でスピンーパリティが$$J^{PC}=0^{++}$$, $$1^{+-}$$, $$2^{++}$$の各チャネルに2個ずつ共鳴が存在することを明らかにした。しかし、これらの共鳴は最近の実験で見つかった$$X(6900)$$と比べると100MeV近く高いところに存在していることが解った。


Weinberg operator contribution to the $$CP$$-odd nuclear force in the quark model

山中 長閑*; 岡 眞

Physical Review D, 106(7), p.075021_1 - 075021_15, 2022/10

 被引用回数:0 パーセンタイル:0.01(Astronomy & Astrophysics)



Nuclear pasta structures at high temperatures

Xia, C.-J.*; 丸山 敏毅; 安武 伸俊*; 巽 敏隆*

Physical Review D, 106(6), p.063020_1 - 063020_14, 2022/09

 被引用回数:1 パーセンタイル:0.01(Astronomy & Astrophysics)

We study nuclear pasta structures at high temperatures within a relativistic mean field model and Thomas-Fermi approximation. Typical structures (droplet, rod, slab, tube, and bubble) are obtained, which form various crystalline configurations. The properties of those nuclear pastas are examined in a three-dimensional geometry with reflection symmetry, where the optimum lattice constants are fixed minimizing the free energy under spherical or cylindrical approximations for Wigner-Seitz cells. For fixed densities and temperatures, the differences of the free energies per baryon for various shapes and lattice structures are typically on the order of tens of keV, suggesting the coexistence of those structures. If we further increase temperature, eventually the non-uniform structures of nuclear pasta become unstable and are converted into uniform nuclear matter. The phase diagrams of nuclear matter are estimated, which is useful for understanding the various phenomena in neutron stars.


Beam dynamics studies for fast beam trip recovery of the Japan Atomic Energy Agency accelerator-driven subcritical system

Yee-Rendon, B.; 近藤 恭弘; 田村 潤; 中野 敬太; 前川 藤夫; 明午 伸一郎

Physical Review Accelerators and Beams (Internet), 25(8), p.080101_1 - 080101_17, 2022/08

 被引用回数:1 パーセンタイル:67.14(Physics, Nuclear)



$$phi$$ meson properties in nuclear matter from QCD sum rules with chirally separated four-quark condensates

Kim, J.*; Gubler, P.; Lee, S. H.*

Physical Review D, 105(11), p.114053_1 - 114053_9, 2022/06

 被引用回数:0 パーセンタイル:0.01(Astronomy & Astrophysics)

The modification of the $$phi$$ meson spectrum in nuclear matter is studied in an updated QCD sum rule analysis, taking into account recent improvements in properly treating the chiral invariant and breaking components of four-quark condensates. Allowing both mass and decay width to change at finite density, the QCD sum rule analysis determines certain combinations of changes for these parameters that satisfy the sum rules equally well. A comprehensive error analysis, including uncertainties related to the behavior of various condensates at linear order in density, the employed renormalization scale and perturbative corrections of the Wilson coefficients, is used to compute the allowed ranges of these parameter combinations. We find that the $$phi$$ meson mass shift in nuclear matter is especially sensitive to the strange sigma term $$sigma_{sN}$$, which determines the decrease of the strange quark condensate in nuclear matter.


Large antisymmetric interlayer exchange coupling enabling perpendicular magnetization switching by an in-plane magnetic field

増田 啓人*; 関 剛斎*; 山根 結太*; Modak, R.*; 内田 健一*; 家田 淳一; Lau, Y.-C.*; 深見 俊輔*; 高梨 弘毅

Physical Review Applied (Internet), 17(5), p.054036_1 - 054036_9, 2022/05

 被引用回数:1 パーセンタイル:0(Physics, Applied)



Heavy-quark spin polarization induced by the Kondo effect in a magnetic field

末永 大輝*; 荒木 康史; 鈴木 渓; 安井 繁宏*

Physical Review D, 105(7), p.074028_1 - 074028_19, 2022/04

 被引用回数:0 パーセンタイル:0.01(Astronomy & Astrophysics)

本論文では、クォーク物質中での近藤効果が、磁場下においてヘビークォークのスピン偏極を誘起する新たなメカニズムを提案する。高密度クォーク物質中では、アップ・ダウン等のライトクォークに対してチャーム・ボトム等のヘビークォークが不純物として働き、カラー交換により相互作用を増幅する「QCD近藤効果」が起こることが理論的に示唆されている。この際にヘビークォークとライトクォークによって構成される近藤凝縮により、ヘビークォークとライトクォークのスピンは混成する。そのため、クォーク物質中でライトクォークが磁場と結合すると、近藤凝縮を介してヘビークォークのスピン偏極も誘起される。このメカニズムを示すため、Nambu-Jona-Lasinio型の相互作用を持つモデルを用い、$$U(1)_{rm EM}$$ゲージ対称性を考慮した頂点補正を加味して計算を行う。これにより磁場下で誘起されるヘビークォークのスピン偏極を線形応答理論に基づいて調べ、近藤効果の発現によってヘビークォークのスピン偏極が如実に誘起されることを示す。これらの結果は今後、符号問題を回避した格子シミュレーションにより検証が期待される。


Design and beam dynamic studies of a 30-MW superconducting linac for an accelerator-driven subcritical system

Yee-Rendon, B.; 近藤 恭弘; 前川 藤夫; 明午 伸一郎; 田村 潤

Physical Review Accelerators and Beams (Internet), 24(12), p.120101_1 - 120101_17, 2021/12

 被引用回数:3 パーセンタイル:53.07(Physics, Nuclear)



Magnetic sensitivity distribution of Hall devices in antiferromagnetic switching experiments

Schreiber, F.*; Meer, H.*; Schmitt, C.*; Ramos, R.*; 齊藤 英治; Baldrati, L.*; Kl$"a$ui, M.*

Physical Review Applied (Internet), 16(6), p.064023_1 - 064023_9, 2021/12

 被引用回数:0 パーセンタイル:0(Physics, Applied)

We analyze the complex impact of the local magnetic spin texture on the transverse Hall-type voltage in device structures utilized to measure magnetoresistance effects. We find a highly localized and asymmetric magnetic sensitivity in the eight-terminal geometries that are frequently used in current-induced switching experiments, for instance, to probe antiferromagnetic materials. Using current-induced switching of antiferromagnetic NiO/Pt as an example, we estimate the change in the spin Hall magnetoresistance signal associated with switching events based on the domain-switching patterns observed via direct imaging. This estimate correlates with the actual electrical data after subtraction of a nonmagnetic contribution. Here, the consistency of the correlation across three measurement geometries with fundamentally different switching patterns strongly indicates a magnetic origin of the measured and analyzed electrical signals.


Study of $$e^+e^-to Upsilon(rm1S,2S)eta$$ and $$e^+e^-to Upsilon(rm 1S)eta^{prime}$$ at $$sqrt{s}=10.866$$ GeV with the Belle detector

Kovalenko, E.*; 谷田 聖; Belle Collaboration*; 他181名*

Physical Review D, 104(11), p.112006_1 - 112006_12, 2021/12

 被引用回数:0 パーセンタイル:0.01(Astronomy & Astrophysics)

We report the first observation of the processes $$e^+e^-toUpsilon(rm 1S,2S)eta$$ at $$sqrt{s}$$=10.866 GeV with a $$10.2sigma$$ and $$16.5sigma$$ significance respectively. The measured Born cross sections are $$sigma(e^+e^- to Upsilon(2S)eta)=2.07 pm 0.21 pm 0.19$$ pb, and $$sigma(e^+e^- to Upsilon(rm 1S)eta)=0.42 pm 0.08 pm 0.04$$ pb. We also set the upper limit on the cross section of the process $$e^+e^- to Upsilon(rm 1S)eta^{prime}$$ to be $$sigma(e^+e^- to Upsilon(rm 1S)eta^{prime}) < 0.035$$~pb at $$90%$$ CL. The results are obtained with the data sample collected with the Belle detector at the KEKB asymmetric-energy $$e^+e^-$$ collider in the energy range from 10.63 GeV to 11.02 GeV.


Measurements of $$q^2$$ moments of inclusive $$B rightarrow X_c ell^+ nu_{ell}$$ decays with hadronic tagging

van Tonder, R.*; 谷田 聖; Belle Collaboration*; 他202名*

Physical Review D, 104(11), p.112011_1 - 112011_32, 2021/12

 被引用回数:3 パーセンタイル:46.7(Astronomy & Astrophysics)

We present the measurement of the first to fourth order moments of the four-momentum transfer squared, $$q^2$$, of inclusive $$B rightarrow X_c ell^+ nu_{ell}$$ decays using the full Belle data set of 711 $$mathrm{fb}^{-1}$$ of integrated luminosity at the $$Upsilon(4S)$$ resonance where $$ell = e, mu$$. The determination of these moments and their systematic uncertainties open new pathways to determine the absolute value of the CKM matrix element $$V_{cb}$$ using a reduced set of matrix elements of the heavy quark expansion. In order to identify and reconstruct the $$X_c$$ system, we reconstruct one of the two $$B$$-mesons using machine learning techniques in fully hadronic decay modes. The moments are measured with progressively increasing threshold selections on $$q^2$$ starting with a lower value of 3.0 $$mathrm{GeV}^2$$ in steps of 0.5 $$mathrm{GeV}^2$$ up to a value of 10.0 $$mathrm{GeV}^2$$. The measured moments are further unfolded, correcting for reconstruction and selection effects as well as QED final state radiation. We report the moments separately for electron and muon final states and observe no lepton flavor universality violating effects.


Revisit the isospin violating decays of $$X$$(3872)

Meng, L.*; Wang, G.-J.*; Wang, B.*; Zhu, S.-L.*

Physical Review D, 104(9), p.094003_1 - 094003_8, 2021/11

 被引用回数:7 パーセンタイル:64.11(Astronomy & Astrophysics)



Kondo effect with Wilson fermions

石川 力*; 中山 勝政*; 鈴木 渓

Physical Review D, 104(9), p.094515_1 - 094515_11, 2021/11

 被引用回数:1 パーセンタイル:18.72(Astronomy & Astrophysics)

「ウィルソン・フェルミオン」と呼ばれる格子上のフェルミ粒子に対する近藤効果を記述する模型を構築し、様々な物理現象の予言・解明を行った。模型として、軽いウィルソン・フェルミオンと重いフェルミオンとの4点相互作用を含むカイラルGross-Neveu模型に対する平均場アプローチを用いた。結果として、ゼロ質量のウィルソン・フェルミオンからなる有限密度媒質において近藤効果が実現可能であることを示し、それに伴う近藤凝縮と軽いフェルミオン対の凝縮(スカラー凝縮)との共存相が存在可能であることを示した。このとき、スカラー凝縮が消える臨界的な化学ポテンシャルの値は近藤効果によってシフトする。さらに、負質量を持つウィルソン・フェルミオンにおいては、パリティ対称性が自発的に破れた相(Aoki phase)が生じることが知られているが、Aoki phaseが生じるパラメータ領域近傍で近藤効果も増幅されることを示した。本研究の発見は、ディラック半金属,トポロジカル絶縁体などの物質や、将来的な格子シミュレーションにおける不純物の役割を明らかにするために役立つことが期待される。


Search for $$B^{0} to tau^pm ell^mp$$ ($$ell=e,mu$$) with a hadronic tagging method at Belle

Atmacan, H.*; 谷田 聖; Belle Collaboration*; 他219名*

Physical Review D, 104(9), p.L091105_1 - L091105_9, 2021/11

 被引用回数:1 パーセンタイル:18.72(Astronomy & Astrophysics)

We present a search for the lepton-flavor-violating decays $$B^{0} to tau^pm ell^mp$$, where $$ell=(e,,mu)$$, using the full data sample of $$772 times 10^6$$ $$B overline{B}$$ pairs recorded by the Belle detector at the KEKB asymmetric-energy $$e^+e^-$$ collider. We use events in which one $$B$$ meson is fully reconstructed in a hadronic decay mode. The $$tau^pm$$ lepton is reconstructed indirectly using the momentum of the reconstructed $$B$$ and that of the $$ell^mp$$ from the signal decay. We find no evidence for $$B^{0} to tau^pm ell^mp$$ decays and set upper limits on their branching fractions at 90% confidence level of $$cal B$$($$B^{0} to tau^pm mu^{mp}$$)$$ < 1.5 times 10^{-5}$$ and $$cal B$$($$B^{0} to tau^pm e^{mp}$$)$$ < 1.6 times 10^{-5}$$.


Measurement of the branching fraction of $$Lambda_c^+ to p omega$$ decay at Belle

Li, S. X.*; 谷田 聖; Belle Collaboration*; 他193名*

Physical Review D, 104(7), p.072008_1 - 072008_8, 2021/10

 被引用回数:1 パーセンタイル:18.72(Astronomy & Astrophysics)

Using 980.6 $$rm fb^{-1}$$ of data collected with the Belle detector operating at the KEKB asymmetric-energy $$e^+e^-$$ collider, we present a measurement of the branching fraction of the singly Cabibbo-suppressed decay $$Lambda_c^+ to p omega$$. A clear $$Lambda_c^+$$ signal is observed for $$Lambda_c^+ to p omega$$ with a statistical significance of 9.1 standard deviations, and we measure the ratio of branching fractions $${cal B}(Lambda_c^+ to p omega)/{cal B}(Lambda_c^+ to p K^- pi^+) = (1.32 pm 0.12 (rm stat) pm 0.10 (rm syst))times 10^{-2}$$, from which we infer the branching fraction $${cal B}(Lambda_c^+ to p omega) = (8.27 pm 0.75 (rm stat) pm 0.62 (rm syst) pm 0.42 (rm ref))times 10^{-4}$$. The first quoted uncertainty is statistical, the second systematic, and the third from the reference mode $$Lambda_c^+ to p K^- pi^+$$.


Heavy baryon spectrum with chiral multiplets of scalar and vector diquarks

Kim, Y.*; Liu, Y.-R.*; 岡 眞; 鈴木 渓

Physical Review D, 104(5), p.054012_1 - 054012_18, 2021/09

 被引用回数:4 パーセンタイル:46.7(Astronomy & Astrophysics)

本論文では、スカラー及びベクトルダイクォークのカイラル有効理論を線形シグマ模型に基づいて構成する。有効理論の主な適用として、チャームまたはボトムクォークを1個含むシングルヘビーバリオンの基底状態と励起状態を記述する。ヘビークォーク($$Q=c, b$$)とダイクォーク間の2体ポテンシャルを用いて、ヘビークォーク・ダイクォーク模型を構築し、$$Lambda_Q$$, $$Sigma_Q$$, $$Xi^{(')}_Q$$, $$Omega_Q$$バリオンの正パリティ及び負パリティ状態のスペクトルを求める。ここで、有効理論に含まれる質量や相互作用パラメータは、格子QCDから得られたダイクォーク質量やヘビーバリオンの実験値を用いて決定される。結果として、擬スカラーダイクォーク質量の逆ヒエラルキーに起因して$$Xi_Q$$(フレーバー$$bar{bf 3}$$)の負パリティ励起状態のスペクトルが、$$Lambda_Q$$とは異なる振る舞いを示すことを示す。一方で、$$Sigma_Q, Xi'_Q$$, $$Omega_Q$$(フレーバー$${bf 6}$$)のスペクトルは、$$Lambda_Q$$と同様である。さらに、我々のヘビークォーク・ダイクォーク模型による結果と実験値やクォーク模型による結果との比較を議論する。


Probing the long-range structure of the $$T^{+}_{cc}$$ with the strong and electromagnetic decays

Meng, L.*; Wang, G.-J.*; Wang, B.*; Zhu, S.-L.*

Physical Review D, 104(5), p.L051502_1 - L051502_8, 2021/09

 被引用回数:35 パーセンタイル:98.71(Astronomy & Astrophysics)



Evidence for the decay $$Omega_{c}^{0} to pi^+Omega(2012)^- to pi^+ (bar{K}Xi)^{-}$$

Li, Y.*; 谷田 聖; Belle Collaboration*; 他190名*

Physical Review D, 104(5), p.052005_1 - 052005_9, 2021/09

 被引用回数:2 パーセンタイル:34.27(Astronomy & Astrophysics)

Using a data sample of 980~fb$$^{-1}$$ collected with the Belle detector operating at the KEKB asymmetric-energy $$e^+e^-$$ collider, we present evidence for the $$Omega(2012)^-$$ in the resonant substructure of $$Omega_{c}^{0} to pi^+ (bar{K}Xi)^{-}$$ ($$(bar{K}Xi)^{-}$$ = $$K^-Xi^0$$ + $$bar{K}^0 Xi^-$$) decays. The significance of the $$Omega(2012)^-$$ signal is 4.2$$sigma$$ after considering the systematic uncertainties. The ratio of the branching fraction of $$Omega_{c}^{0} to pi^{+} Omega(2012)^- to pi^+ (bar{K}Xi)^{-}$$ relative to that of $$Omega_{c}^{0} to pi^{+} Omega^-$$ is calculated to be 0.220 $$pm$$ 0.059(stat.) $$pm$$ 0.035(syst.). The individual ratios of the branching fractions of the two isospin modes are also determined, and found to be $${cal B}(Omega_{c}^0 to pi^+ Omega(2012)^-) times {cal B}(Omega(2012)^- to K^-Xi^0)/{cal B}(Omega_{c}^0 to pi^+ K^- Xi^0)$$ =(9.6 $$pm$$ 3.2(stat.) $$pm$$ 1.8(syst.))% and $${cal B}(Omega_{c}^0 to pi^+ Omega(2012)^-) times {cal B}(Omega(2012)^- to bar{K}^0 Xi^-)/{cal B}(Omega_{c}^0 to pi^+ bar{K}^0 Xi^-)$$ = (5.5 $$pm$$ 2.8(stat.) $$pm$$ 0.7(syst.))%.


Measurement of the masses and widths of the $$Sigma_c(2455)^+$$ and $$Sigma_c(2520)^+$$ baryons

Yelton, J.*; 谷田 聖; Belle Collaboration*; 他205名*

Physical Review D, 104(5), p.052003_1 - 052003_8, 2021/09

 被引用回数:0 パーセンタイル:0.01(Astronomy & Astrophysics)

Using 980 $${rm fb}^{-1}$$ of data ${collected}$ with the Belle detector operating at the KEKB asymmetric-energy $$e^+e^-$$ collider, we report the measurements of the masses, and the first measurements of the instrinsic widths, of the $$Sigma_c(2455)^+$$ and $$Sigma_c(2520)^+$$ charmed baryons. We find $$M(Sigma_c(2455)^+)-M(Lambda_c^+) = 166.17pm 0.05^{+0.16}_{-0.07} {rm MeV}/c^2$$, $$Gamma(Sigma_c(2455)^+) = 2.3 pm 0.3 pm 0.3 {rm MeV/c^2}$$, $$M(Sigma_c(2520)^+)-M(Lambda_c^+) = 230.9 pm 0.5 ^{+0.5}_{-0.1} {rm MeV}/c^2$$, and $$Gamma(Sigma_c(2520)^+) = 17.2^{+2.3 +3.1}_{-2.1 -0.7} {rm MeV}/c^2$$, where the uncertainties are statistical and systematic, respectively. These measurements can be used to test models of the underlying quark structure of the $$Sigma_c$$ states.

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