A5081842650- Topological Materials and Phenomena
- Quantum and electron transport phenomena
- Graphene research and applications
- Electronic and Structural Properties of Oxides
- Iron-based superconductors research
- Semiconductor materials and devices
- Advancements in Semiconductor Devices and Circuit Design
- Advanced Condensed Matter Physics
- Magnetic confinement fusion research
- Physics of Superconductivity and Magnetism
- Multiferroics and related materials
- Magnetic and transport properties of perovskites and related materials
- Semiconductor materials and interfaces
- Superconductivity in MgB2 and Alloys
- Ionosphere and magnetosphere dynamics
- 2D Materials and Applications
- Semiconductor Quantum Structures and Devices
- Magnetic properties of thin films
- Thermodynamic and Structural Properties of Metals and Alloys
- Plasma Diagnostics and Applications
- Quantum many-body systems
- Nuclear materials and radiation effects
- Chemical and Physical Properties of Materials
- Particle accelerators and beam dynamics
- Inorganic Chemistry and Materials
The University of Tokyo
1996-2024
Tokyo Institute of Technology
2021-2022
The Graduate University for Advanced Studies, SOKENDAI
2015-2017
Max Planck Institute for Plasma Physics - Greifswald
2015
Shiga University of Medical Science Hospital
2006
Searching for an ideal magnetic Weyl semimetal hosting only a single pair of points has been focal point systematic clarification its unique magnetotransport derived from the interplay between topology and magnetization. Among candidates, triangular-lattice antiferromagnet EuCd2As2 attracting special attention due to prediction phase in ferromagnetic state; however, transport properties low-carrier density samples have remained elusive. Here, we report molecular beam epitaxy growth films,...
Here we study nonmonotonic features which appear both in magnetoresistivity and anomalous Hall resistivity during the simple magnetization process, by systematically measuring type-II magnetic Weyl semimetal EuCd$_2$Sb$_2$ films over a wide carrier density range. We find that positive hump can be explained as manifestation of field-linear term generalized magnetoconductivity formula including Berry curvature. As also confirmed model calculation, negative pronounced near point energy case...
Geometrical frustration endows magnets with degenerate ground states, resulting in exotic spin structures and quantum phenomena. Such magnets, called can display non-coplanar textures be a viable platform for the topological Hall effect driven by “emergent field.” However, most are insulators, making it challenging to electrically detect associated fluctuations excitations. Here, we probe magnetic transitions ice insulator Dy 2 Ti O 7 , prototypical magnet, as emergent magnetotransport...
While anomalous Hall effect (AHE) has been extensively studied in the past, efforts for realizing large response have mainly limited within intrinsic mechanism. Lately, however, a theory of extrinsic mechanism predicted that magnetic scattering by spin cluster can induce AHE even above ordering temperature, particularly semiconductors with low carrier density, strong exchange coupling, and finite chirality. Here, we find out new semiconductor EuAs, where Eu2+ ions moments form distorted...
A large intrinsic anomalous Hall effect (AHE) originating in the Berry curvature has attracted growing attention for potential applications. The recently proposed magnetic Weyl semimetal ${\mathrm{EuCd}}_{2}{\mathrm{Sb}}_{2}$ provides an excellent platform controlling AHE because it only hosts a Weyl-point-related band structure near Fermi energy. Here, we report fabrication of single-crystalline films and control their by film technique. As also analyzed first-principles calculations...
We present an epitaxial stabilization of pyrochlore Bi$_2$Rh$_2$O$_7$ on Y-stabilized ZrO$_2$ (YSZ) (111) substrate by inserting a Eu$_2$Ti$_2$O$_7$ template layer, otherwise Bi-based layered structures being formed directly YSZ substrate. This result reveals that "iso-structural crystal phase" plays important role in the interfacial phase control. The film exhibits $p$-type electrical conduction with lowest longitudinal resistivity ($\rho_\mathrm{xx}$) among reported Rh oxides. Such...
We present a study on magnetotransport in films of the topological Dirac semimetal Cd$_{3}$As$_{2}$ doped with Sb grown by molecular beam epitaxy. In our weak antilocalization analysis, we find significant enhancement spin-orbit scattering rate, indicating that doping leads to strong increase pristine band-inversion energy. discuss possible origins this large comparing Sb-doped other compound semiconductors. will be suitable system for further investigations and functionalization semimetals.
Layered oxides have been intensively studied due to their high degree of freedom in designing various electromagnetic properties and functionalities. While Bi-based layered supercell (LSC) compounds [BinOn+δ]-[MO2] (M = Mn, Mn/Al, Mn/Fe, or Mn/Ni; n 2, 3) are a group prospective candidates, all the reported insulators. Here, we report on synthesis two novel metallic LSC [BinOn+δ]-[RhO2] (n by pulsed laser deposition subsequent annealing. With tuning thickness sublattice from Bi2O2+δ Bi3O3+δ,...
While the family of layered pnictides $ABX_2$ ($A$ : rare or alkaline earth metals, $B$ transition $X$ Sb/Bi) can host Dirac dispersions based on Sb/Bi square nets, nearly half them has not been synthesized yet for possible combinations $A$ and cations. Here we report fabrication EuCdSb$_{\mathrm{2}}$ with largest $B$-site ionic radius, which is stabilized first time in thin film form by molecular beam deposition. crystallizes an orthorhombic $Pnma$ structure exhibits antiferromagnetic...
Searching for an ideal magnetic Weyl semimetal hosting only a single pair of points has been focal point systematic clarification its unique magnetotransport derived from the interplay between topology and magnetization. Among candidates, triangular-lattice antiferromagnet EuCd$_2$As$_2$ attracting special attention due to prediction phase in ferromagnetic state, however, transport properties low-carrier density samples have remained elusive. Here we report molecular beam epitaxy growth...
We report fabrication of ${\mathrm{EuSb}}_{2}$ single-crystalline films and investigation their quantum transport. First-principles calculations demonstrate that is a magnetic topological nodal-line semimetal protected by nonsymmorphic symmetry. Observed Shubnikov-de Haas oscillations with multiple frequency components exhibit small effective masses two-dimensional field-angle dependence even in 250 nm thick film, further suggesting possible contributions surface states. This finding the...
We investigated non-resonant phonon-assisted tunnelling in an InGaAs/InAlAs triple barrier diode the presence of high magnetic fields up to 40 T current direction. observe quenching valley and narrow band GaAs-like AlAs-like longitudinal optical (LO) phonon peaks related bottleneck effect. The peak-to-valley ratio device increases significantly 12 T. LO-phonon give information about electron - coupling strength well layers.
The impact of epitaxial NiSi <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> S/D on MOSFET performance has been investigated. Atomically flat /Si (111)-facet interface and straight edges irrespective the gate edge roughness contribute to suppressing SCE
Layered oxides have been intensively studied due to their high degree of freedom in designing various electromagnetic properties and functionalities. While Bi-based layered supercell (LSC) compounds [Bi$_n$O$_{n+\delta}$]-[$M$O$_2$] ($M$ = Mn, Mn/Al, Mn/Fe, or Mn/Ni; $n=2, 3$) are a group prospective candidates, all the reported insulators. Here, we report on synthesis two novel metallic LSC [Bi$_{n}$O$_{n+\delta}$]-[RhO$_2$] ($n=2, by pulsed laser deposition subsequent annealing. With...
Large intrinsic anomalous Hall effect (AHE) originating in the Berry curvature has attracted growing attention for potential applications. Recently proposed magnetic Weyl semimetal EuCd$_2$Sb$_{\mathrm{2}}$ provides an excellent platform controlling AHE because it only hosts a Weyl-points related band structure near Fermi energy. Here we report fabrication of single-crystalline films and control their by film technique. As also analyzed first-principles calculations energy-dependent...