15 citations · 15 across the 1 of their papers we have counts for
8 papers
Topological charge pumping in quasiperiodic systems characterized by Bott index
Mao Yoshii, Sota Kitamura, Takahiro Morimoto
We study topological charge pumping in one-dimensional quasiperiodic systems. Since these systems lack periodicity, we cannot use the conventional approach based on the topological…
Electric polarization and nonlinear optical effects in noncentrosymmetric magnets
Takahiro Morimoto, Sota Kitamura, Shun Okumura
We study electric polarization and nonlinear optical effects in spin systems with broken inversion symmetry. We apply strong coupling expansion to the underlying electronic Hamilto…
Current response of nonequilibrium steady states in Landau-Zener problem: Nonequilibrium Green's function approach
Sota Kitamura, Naoto Nagaosa, Takahiro Morimoto
The carrier generation in insulators subjected to strong electric fields is characterized by the Landau-Zener formula for the tunneling probability with a nonperturbative exponent.…
Nonreciprocal Landau-Zener tunneling
Sota Kitamura, Naoto Nagaosa, Takahiro Morimoto
Application of strong dc electric field to an insulator leads to quantum tunneling of electrons from the valence band to the conduction band, which is a famous nonlinear response k…
Hidden kagome-lattice picture and origin of high conductivity in delafossite PtCoO
Hidetomo Usui, Masayuki Ochi, Sota Kitamura +8
We study the electronic structure of delafossite PtCoO to elucidate its extremely small resistivity and high mobility. The band exhibits steep dispersion near the Fermi level d…
Spin Hall effect in 2D metallic delafossite PtCoO and vicinity topology
Sota Kitamura, Hidetomo Usui, Robert-Jan Slager +9
The two-dimensional (2D) metal PtCoO is renowned for the lowest room temperature resistivity among all oxides, close to that of the top two materials Ag and Cu. In addition, we…