1k citations · 2.3k across the 24 of their papers we have counts for
24 papers
Two-dimensional superconducting diode effect in topological insulator/superconductor heterostructure
Soma Nagahama, Yuki Sato, Minoru Kawamura +7
The superconducting diode effect (SDE) is characterized by the nonreciprocity of Cooper-pair motion with respect to current direction. In three-dimensional (3D) materials, SDE resu…
Quantum geometry in low-energy linear and nonlinear optical responses of magnetic Rashba semiconductor (Ge,Mn)Te
Tsubasa Takagi, Hikaru Watanabe, Ryutaro Yoshimi +7
Quantum geometry appears as a key factor in understanding the optical properties of quantum materials, with the anticipation on diverging or quantized responses near the Dirac and…
Control of nonreciprocal charge transport in topological insulator/superconductor heterostructures with Fermi level tuning and superconducting-layer thickness
Soma Nagahama, Yuki Sato, Minoru Kawamura +7
Nonreciprocal charge transport (NCT) is defined as a phenomenon where electrical resistance depends on the current direction. It has been drawing much attention because it sensitiv…
Non-Fermi liquid transport and strong mass enhancement near the nematic quantum critical point in FeSeTe thin films
Yuki Sato, Soma Nagahama, Ilya Belopolski +10
Unconventional superconductivity is often accompanied by non-Fermi liquid (NFL) behavior, which emerges near a quantum critical point (QCP) - a point where an electronic ordered ph…
Emergence of ferroelectric topological insulator as verified by quantum Hall effect of surface states in (Sn,Pb,In)Te films
Ryutaro Yoshimi, Ryosuke Kurihara, Yoshihiro Okamura +9
Emergent phenomena arising from nontrivial band structures based on topology and symmetry have been attracting keen interest in contemporary condensed-matter physics. Materials suc…
This took us a Weyl: synthesis of a semimetallic Weyl ferromagnet with point Fermi surface
Ilya Belopolski, Ryota Watanabe, Yuki Sato +19
Quantum materials governed by emergent topological fermions have become a cornerstone of physics. Dirac fermions in graphene form the basis for moiré quantum matter, and Dirac ferm…
Molecular beam epitaxy of superconducting FeSeTe thin films interfaced with magnetic topological insulators
Yuki Sato, Soma Nagahama, Ilya Belopolski +7
Engineering heterostructures with various types of quantum materials can provide an intriguing playground for studying exotic physics induced by the proximity effect. Here, we repo…
Gate-electric-field and magnetic-field control of versatile topological phases in a semi-magnetic topological insulator
Ryota Watanabe, Ryutaro Yoshimi, Kei S. Takahashi +4
Surface states of a topological insulator demonstrate interesting quantum phenomena, such as the quantum anomalous Hall (QAH) effect and the quantum magnetoelectric effect. Fermi e…
Nonreciprocal electrical transport in multiferroic semiconductor (Ge,Mn)Te
Ryutaro Yoshimi, Minoru Kawamura, Kenji Yasuda +4
We have investigated the nonreciprocal electrical transport, that is a nonlinear resistance effect depending on the current direction, in multiferroic Rashba semiconductor (Ge,Mn)T…
Versatile electronic states in epitaxial thin films of (Sn-Pb-In)Te: from topological crystalline insulator and polar semimetal to superconductor
Ryutaro Yoshimi, Makoto Masuko, Naoki Ogawa +5
Epitaxial thin films of (SnPb)InTe were successfully grown by molecular-beam-epitaxy (MBE) in a broad range of compositions (0 x 1, 0 $\le…
Molecular beam epitaxy of superconducting SnInTe thin films
M. Masuko, R. Yoshimi, A. Tsukazaki +4
We report a systematic study on the growth conditions of SnInTe thin films by molecular beam epitaxy for maximization of superconducting transition temperature $T_\math…
Current scaling of the topological quantum phase transition between a quantum anomalous Hall insulator and a trivial insulator
Minoru Kawamura, Masataka Mogi, Ryutaro Yoshimi +5
We report a current scaling study of a quantum phase transition between a quantum anomalous Hall insulator and a trivial insulator on the surface of a heterostructure film of magne…
Characterization of Sr2RuO4 Josephson junctions made of epitaxial films
Masaki Uchida, Ikkei Sakuraba, Minoru Kawamura +4
We have studied fundamental properties of weak-link Sr2RuO4/Sr2RuO4 Josephson junctions fabricated by making a narrow constriction on superconducting Sr2RuO4 films through laser mi…
Quantum anomalous Hall effect driven by magnetic proximity coupling in all-telluride based heterostructure
Ryota Watanabe, Ryutaro Yoshimi, Minoru Kawamura +7
The quantum anomalous Hall effect (QAHE) is an exotic quantum phenomenon originating from dissipation-less chiral channels at the sample edge. While the QAHE has been observed in m…
Large Anomalous Hall Effect in Topological Insulators with Proximitized Ferromagnetic Insulators
Masataka Mogi, Taro Nakajima, Victor Ukleev +9
We report a proximity-driven large anomalous Hall effect in all-telluride heterostructures consisting of ferromagnetic insulator Cr2Ge2Te6 and topological insulator (Bi,Sb)2Te3. De…
Topological quantum phase transition in magnetic topological insulator upon magnetization rotation
Minoru Kawamura, Masataka Mogi, Ryutaro Yoshimi +5
We report a continuous phase transition between quantum-anomalous-Hall and trivial-insulator phases in a magnetic topological insulator upon magnetization rotation. The Hall conduc…
Tailoring tricolor structure of magnetic topological insulator for robust axion insulator
M. Mogi, M. Kawamura, A. Tsukazaki +4
Exploration of novel electromagnetic phenomena is a subject of great interest in topological quantum materials. One of the unprecedented effects to be experimentally verified is to…
Quantized chiral edge conduction on reconfigurable domain walls of a magnetic topological insulator
K. Yasuda, M. Mogi, R. Yoshimi +5
The electronic orders in magnetic and dielectric materials form the domains with different signs of order parameters. The control of configuration and motion of the domain walls (D…
Current-driven instability of quantum anomalous Hall effect in ferromagnetic topological insulators
Minoru Kawamura, Ryutaro Yoshimi, Atsushi Tsukazaki +3
Instability of quantum anomalous Hall (QAH) effect has been studied as function of electric current and temperature in ferromagnetic topological insulator thin films. We find that…
Effective Carrier Doping and Metallization in LaxSr2-x-yBayIrO4-delta Thin Films
M. Ito, M. Uchida, Y. Kozuka +2
We fabricate LaxSr2-x-yBayIrO4-delta thin films by pulsed laser deposition, in an effort to realize the effective carrier doping and metallization in the Sr2IrO4 system. We design…
Enhanced photogalvanic current in topological insulators via Fermi energy tuning
K. N. Okada, N. Ogawa, R. Yoshimi +4
We achieve the enhancement of circular photogalvanic effect arising from the photo-injection of spins in topological insulator thin films by tuning the Fermi level (). A…
Magnetic modulation doping in topological insulators toward higher-temperature quantum anomalous Hall effect
M. Mogi, R. Yoshimi, A. Tsukazaki +5
Quantum anomalous Hall effect (QAHE), which generates dissipation-less edge current without external magnetic field, is observed in magnetic-ion doped topological insulators (TIs),…
Electronic correlations and Hund's coupling effects in SrMoO revealed by photoemission spectroscopy
H. Wadati, K. Yoshimatsu, H. Kumigashira +10
We investigate the electronic structure of a perovskite-type Pauli paramagnet SrMoO3 (t2g2) thin film using hard x-ray photoemission spectroscopy and compare the results to the rea…
Anomalous Hall Effect and Magnetic Monopoles in Momentum-Space
Z. Fang, N. Nagaosa, K. S. Takahashi +7
Efforts to find the magnetic monopole in real space have been made in cosmic rays and in accelerators, but up to now there is no firm evidence for its existence due to the very hea…