Article
Materials Science, Multidisciplinary
Xiaohui Wang, Wei Luo
Summary: The topological pumping effect in multi-Weyl semimetals modulated by two orthogonal ac electric fields was investigated. It was found that the pumping effect is isotropic regardless of the anisotropic energy-momentum relation, and a charge current could be measured by using a valley-polarized electrode.
RESULTS IN PHYSICS
(2021)
Article
Physics, Multidisciplinary
Alvaro Diaz-Fernandez, Francisco Dominguez-Adame, Oscar de Abril
Summary: In this study, the effect of a single magnetic impurity in Weyl semimetals is discussed as a first step towards considering a larger number of point-like impurities. Resonances in the local density of states are found, along with anisotropic spin textures observed in the spin-resolved LDOS. These results can pave the way for further studies involving a large number of random magnetic impurities.
NEW JOURNAL OF PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Chuanchang Zeng, Snehasish Nandy, Sumanta Tewari
Summary: This study systematically investigates the BCD in 3D WSMs using lattice Weyl Hamiltonians and finds that the nonzero BCD and its related important features are not dependent on the contribution from the Weyl nodes, but rather on the part of the Fermi surface lying between the Weyl nodes. Additionally, specific experimental signatures of BCD-induced transport in WSMs, such as nonlinear anomalous Hall, Nernst, and thermal Hall effects, are predicted and can be directly checked in experiments.
Article
Materials Science, Multidisciplinary
Rui-Hao Li, Olle G. Heinonen, Anton A. Burkov, Steven S-L Zhang
Summary: In certain Weyl semimetals with broken inversion symmetry, a nonlinear Hall effect is predicted to occur when the energy dispersions around pairs of Weyl nodes are skewed, leading to tilted Weyl cones. This Hall conductivity, which is linear in both electric and magnetic fields, is critically dependent on the tilting of the Weyl cones, and does not rely on a finite Berry curvature dipole.
Article
Materials Science, Multidisciplinary
D. Schmeltzer, Avadh Saxena
Summary: The study investigates the Weyl semimetal in a constant magnetic field, focusing on interactions between different Landau levels and chiralities. By considering factors such as electron-phonon coupling and chiral anomaly, the theory explores how the sliding phase is controlled by the electric field. These interactions give rise to a sliding charge density wave in a Weyl semimetal with two nodes along the direction of the applied magnetic field.
Article
Materials Science, Multidisciplinary
Predrag Nikolic
Summary: The decay of spin waves into Stoner excitations in magnetic Weyl semimetals is found to have a universal dependence on frequency, momentum, and parameters characterizing the relativistic Weyl spectrum. The absence of uniform Gilbert damping by Weyl electrons is also noted. Using the s-d model, the decay rate of spin waves is calculated perturbatively, allowing for indirect inference of details of the Weyl spectrum through probing local moments with inelastic neutron scattering.
Article
Physics, Multidisciplinary
J. Schusser, H. Bentmann, M. Uenzelmann, T. Figgemeier, C. -H Min, S. Moser, J. N. Neu, T. Siegrist, F. Reinert
Summary: This study combines state-of-the-art photoemission theory with experimental results to investigate the electronic structure of Weyl semimetals TaAs and TaP. The findings suggest that previous surface-band-counting schemes for identifying nonzero Chern numbers are ambiguous, while dichroic ARPES provides a more accurate approach to determine Fermi arcs.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Matej Badin
Summary: In this study, we investigate many-body versions of Landau-Zener-like problems of non-interacting electrons in several k center dot p models representing Weyl and Dirac semimetals. We systematically include non-adiabatic corrections to the quantum limit of chiral charge pumping in these models. Our findings show that the non-adiabatic corrections non-trivially manifest the relative homotopy invariant and Euler class invariant in the quantum limit of chiral charge pumping. These corrections can potentially affect conductivity channels associated with the chiral anomaly. Moreover, we demonstrate that, for non-symmorphic systems, this contribution is sensitive to the direction of the applied magnetic field, suggesting a strongly anisotropic longitudinal magnetoresistance due to the conjectured direction-selective chiral anomaly.
Article
Materials Science, Multidisciplinary
Yuriy G. Semenov, Xinyi Xu, James A. Boulton, Ki Wook Kim
Summary: This study proposes the possibility of realizing DMI through electrical modulation in magnetic Weyl semimetals. By utilizing an alternative mechanism of the antisymmetric indirect spin-spin interaction, which can be sensitive to external electric and magnetic fields through the redistribution of Weyl fermions, this approach becomes particularly prominent in WSMs with inversion symmetry.
Article
Materials Science, Multidisciplinary
Bao-Qin Wang, Hong Wu, Jun-Hong An
Summary: By periodic driving, novel SOTSMs and hybrid-order Weyl semimetals can be created, featuring adjustable nodes and hinge Fermi arcs. These materials provide a convenient way to synthesize exotic topological phases.
Article
Materials Science, Multidisciplinary
Chuanchang Zeng, Snehasish Nandy, Sumanta Tewari
Summary: We discover the nonlinear planar thermal Hall effect and nonlinear planar Nernst effect induced by chiral anomaly in Weyl semimetals. Using the semiclassical Boltzmann transport theory, we derive the analytical expressions for these effects and evaluate the mathematical relations among them.
Article
Materials Science, Multidisciplinary
Hong Lu, Wentao Yang, Yuqing Huang, Yi Bian, Xiao Zhang, Shuang Jia
Summary: Single crystals of Weyl semimetals or candidate RAlGe (R = La, Ce, Pr and Nd) have been synthesized by self-flux method and confirmed to have a non-centrosymmetric LaPtSi-type structure. The magnetic, thermal and electrical properties of RAlGe are strongly influenced by the configurations of localized 4f electrons compared to the non-magnetic LaAlGe. The critical temperatures for magnetic transition in CeAlGe, PrAlGe and NdAlGe are around 5.1 K, 15.4 K and 5.2 K, respectively. PrAlGe and NdAlGe have a c easy axis with similar anisotropy, while the easy direction for CeAlGe lies in the a axis below 12 K. The lambda-shaped specific heat indicates second-order phase transitions. The magnetic entropy for PrAlGe and NdAlGe approaches the values of Hund's ground states at about 60 K and 50 K, while that for CeAlGe reaches 87% of Rln2 at Tc due to a doublet ground state. Combining multiple experiments and effective fittings is significant for exploring the potential application of Weyl RAlGe family in spintronics.
Article
Physics, Condensed Matter
J. X. Zhang, C. M. Wang
Summary: A 2pi-periodic anisotropic magnetoresistance (AMR) violating the classical two-fold symmetry is discovered in multi-Weyl semimetals, induced by the intrinsic magnetization due to magnetic doping. The novel AMR is strongly influenced by the monopole charge. Tilt along the x-direction or equivalently along the y-direction is essential for non-zero AMR in single- and triple-Weyl semimetals, but the untilted double-Weyl case still exhibits AMR with a 2pi period. Furthermore, the conductivity in the triple-Weyl case shows out-of-phase oscillations compared to the other two cases. The decomposition of conductivity into pi and 2pi parts reveals that the amplitude of the dominant 2pi contribution increases linearly with magnetization for all three cases, with the magnitude strongly affected by the strength of magnetic scattering. This research contributes to a deeper understanding of AMR in multi-Weyl semimetals.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Materials Science, Multidisciplinary
Jin Cao, Maoyuan Wang, Zhi-Ming Yu, Yugui Yao
Summary: This study reveals a hidden surface photogalvanic effect in Weyl semimetals, which can generate a large effective three-dimensional shift current in a wide terahertz range. The findings suggest that Weyl semimetals are promising material candidates for developing efficient terahertz photodetectors.
Article
Materials Science, Multidisciplinary
Md Sabbir Akhanda, Sergiy Krylyuk, Diane A. Dickie, Albert V. Davydov, Fei Han, Mingda Li, Mona Zebarjadi
Summary: Resistivity versus temperature measurement is commonly used to identify temperature-induced phase change and hysteresis loop. The Seebeck coefficient is a better probe of the material's phase and is influenced predominantly by the density of states. In MoTe2, the contribution of electrons and holes is observed to compete, and the presence of tungsten instead of molybdenum enhances the contribution of electron pockets. Additionally, MoTe2 exhibits a topologically induced enhancement of the Nernst coefficient at low temperatures, with a relatively large phase-transition induced Thomson coefficient measured at 254 K.
MATERIALS TODAY PHYSICS
(2022)
Article
Multidisciplinary Sciences
Yasufumi Araki
SCIENTIFIC REPORTS
(2018)
Article
Physics, Multidisciplinary
Yasufumi Araki
ANNALEN DER PHYSIK
(2020)
Article
Physics, Multidisciplinary
Yasufumi Araki, Jin Watanabe, Kentaro Nomura
Summary: This study theoretically explores the electronic structure of a magnetic nodal-line state in a topological Dirac semimetal by introducing magnetism. It finds that the system can transition into either a Weyl semimetal or a nodal-line semimetal depending on certain factors, demonstrating zero modes with specific band structures at the boundary which are numerically verified.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2021)
Article
Physics, Multidisciplinary
Daichi Kurebayashi, Yasufumi Araki, Kentaro Nomura
Summary: This study theoretically investigates current- and charge-induced spin torques in magnetic Weyl semimetals. The results show that current-induced spin torques and charge-induced spin torques originate from different physical mechanisms.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2021)
Article
Physics, Multidisciplinary
Yasufumi Araki, Jun'ichi Ieda
Summary: The momentum-space topology of electrons under strong spin-orbit coupling contributes to the electrically induced torques exerted on magnetic textures insensitively to disorder or thermal fluctuation. A direct connection between band topology and torques is presented by classifying the whole torques phenomenologically. Additionally, torques can also emerge intrinsically from the anomalous velocity of electrons regardless of a nonequilibrium transport current.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Michihiko Yamanouchi, Yasufumi Araki, Takaki Sakai, Tetsuya Uemura, Hiromichi Ohta, Jun'ichi Ieda
Summary: In a ferromagnetic Weyl metal, a large effective magnetic field exerted on a magnetic domain wall by current has been reported. The ratio of the effective magnetic field to current density shows a nonmonotonic temperature dependence and surpasses the ratios of conventional spin-transfer torques and spin-orbit torques. This enhancement is well described by the topological Hall torque, which is exerted on the domain wall by Weyl electrons emerging around Weyl points under an applied electric field. The ratio of the effective magnetic field arising from the topological Hall torque to current density is over one order of magnitude higher than that originating from spin-transfer torques and spin-orbit torques in metallic systems, indicating that the topological Hall torque may provide a more energy-efficient way to manipulate magnetization in spintronics devices.
Article
Physics, Multidisciplinary
Jin Watanabe, Yasufumi Araki, Koji Kobayashi, Akihiro Ozawa, Kentaro Nomura
Summary: In this study, we numerically investigated the magnetic orderings on the kagome lattice based on the tight-binding Hamiltonian of electrons. We found that the kagome lattice model can exhibit both ferromagnetic and noncollinear antiferromagnetic orderings depending on the electron filling. Additionally, the spin-orbit coupling plays a crucial role in stabilizing the noncollinear orderings.
JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN
(2022)
Article
Astronomy & Astrophysics
Daiki Suenaga, Yasufumi Araki, Kei Suzuki, Shigehiro Yasui
Summary: We propose a new mechanism for heavy-quark spin polarization in quark matter induced by the Kondo effect under an external magnetic field. Through coupling between light quarks and the magnetic field in quark matter, the HQSP is driven by the Kondo effect. The results show a significant increase in HQSP with the appearance of the Kondo effect, which can be tested in future sign-problem-free lattice simulations.
Article
Physics, Multidisciplinary
Yasufumi Araki, Takahiro Misawa, Kentaro Nomura
Summary: Theoretical proposal of long-range spin transport mediated by surface states of a topological Dirac semimetal. Experimental demonstration of robustness and long-range stability of the proposed scheme for spin transport.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Astronomy & Astrophysics
Daiki Suenaga, Yasufumi Araki, Kei Suzuki, Shigehiro Yasui
Summary: The study reveals that the Kondo effect can catalyze the chiral separation effect in quark matter, with an enhancement observed particularly in the dynamical limit. The presence of heavy impurities plays a crucial role in the transport phenomena of light quarks induced by a magnetic field.
Article
Physics, Multidisciplinary
Yasufumi Araki, Daiki Suenaga, Kei Suzuki, Shigehiro Yasui
Summary: After hybridizing relativistic and nonrelativistic fermions, their spin-orbital crossed susceptibility is modified around the band hybridization point, leading to spin polarization of nonrelativistic fermions. These effects are enhanced under a dynamic magnetic field and can be realized in solids with slight breaking of crystalline symmetry or in quark matter with dilute heavy quarks strongly hybridized with light quarks.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
Yasufumi Araki, Daiki Suenaga, Kei Suzuki, Shigehiro Yasui
Summary: Two different types of relativistic Kondo effects were investigated, with one involving heavy-impurity degrees of freedom and the other introducing heavy-fermion degrees of freedom through heavy-fermion effective theories. The dispersions near the Fermi surface are very similar in both cases, but they differ in structure at low momentum.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Physics, Multidisciplinary
Yasufumi Araki, Takahiro Misawa, Kentaro Nomura
PHYSICAL REVIEW RESEARCH
(2020)
Article
Materials Science, Multidisciplinary
Yasufumi Araki, Akihide Yoshida, Kentaro Nomura
