793 citations · 10.5k across the 194 of their papers we have counts for
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Superconductivity studied by solving ab initio low-energy effective Hamiltonians for carrier doped CaCuO, BiSrCuO, BiSrCaCuO, and HgBaCuO
Michael Thobias Schmid, Jean-Baptiste Morée, Ryui Kaneko +2
We numerically analyze superconductivity (SC) in the cuprate superconductors by using ab initio effective Hamiltonians consisting of the antibonding combination of Cu $3d_{x^2-y^2}…
material design of Ag-based oxides for high- superconductor
Motoaki Hirayama, Michael Thobias Schmid, Terumasa Tadano +2
We propose silver-based oxides with layered perovskite structure as candidates of exhibiting intriguing feature of strongly correlated electrons. The compounds show unique covalenc…
Competition among various charge-inhomogeneous states and d-wave superconducting state in Hubbard models on square lattices
Kota Ido, Takahiro Ohgoe, Masatoshi Imada
We study competitions between charge uniform and inhomogeneous states in two-dimensional Hubbard models by using a variational Monte Carlo method. At realistic parameters for cupra…
Ab initio effective Hamiltonians for cuprate superconductors
Motoaki Hirayama, Youhei Yamaji, Takahiro Misawa +1
Ab initio low-energy effective Hamiltonians of two typical high-temperature copper-oxide superconductors, whose mother compounds are LaCuO and HgBaCuO, are derived…
Correlation-induced superconductivity dynamically stabilized and enhanced by laser irradiation
Kota Ido, Takahiro Ohgoe, Masatoshi Imada
Studies on out-of-equilibrium dynamics have paved a way to realize a new state of matter. Especially, superconductor-like properties above room temperatures recently suggested in c…
Competition among Superconducting, Antiferromagnetic, and Charge Orders with Intervention by Phase Separation in the 2D Holstein-Hubbard Model
Takahiro Ohgoe, Masatoshi Imada
Using a variational Monte Carlo method, we study competitions of strong electron-electron and electron-phonon interactions in the ground state of Holstein-Hubbard model on a square…
Impurity Effects on Superconductivity on Surfaces of Topological Insulators
Yuto Ito, Youhei Yamaji, Masatoshi Imada
A two-dimensional superconductor (SC) on surfaces of topological insulators (TIs) is a mixture of s-wave and helical p-wave components when induced by s-wave interactions, since sp…
High-temperature Superconductivity in Layered Nitrides β-LiMNCl (M = Ti, Zr, Hf): Insights from Density-functional Theory for Superconductors
Ryosuke Akashi, Kazuma Nakamura, Ryotaro Arita +1
We present an ab initio analysis with density functional theory for superconductors (SCDFT) to understand the superconducting mechanism of doped layered nitrides β-LiMNCl (M=Ti…
Stability of Unconventional Superconductivity on Surfaces of Topological Insulators
Yuto Ito, Youhei Yamaji, Masatoshi Imada
Superconductivity on the surface of topological insulators is known to be anisotropic and unconventional in that the symmetry is the mixture of s-wave and nodeless p-wave component…
Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe2As2, LiFeAs, FeSe and FeTe: Electron Correlation and Covalency
Takashi Miyake, Kazuma Nakamura, Ryotaro Arita +1
Effective low-energy Hamiltonians for several different families of iron-based superconductors are compared after deriving them from the downfolding scheme based on first-principle…
Ab initio Derivation of Low-energy Model for Iron-Based Superconductors LaFeAsO and LaFePO
Kazuma Nakamura, Ryotaro Arita, Masatoshi Imada
Effective Hamiltonians for LaFeAsO and LaFePO are derived from the downfolding scheme based on first-principles calculations and provide insights for newly discovered superconducti…
Quantum Mott Transition and Superconductivity
Masatoshi Imada
The gas-liquid transition is a first-order transition terminating at a finite-temperature critical point with diverging density fluctuations. Mott transition, a metal-insulator tra…
Superconductivity Driven by the Interband Coulomb Interaction and Implications for the Superconducting Mechanism of MgB2
Masatoshi Imada
Superconducting mechanism mediated by interband exchange Coulomb repulsion is examined in an extended two-band Hubbard models with a wide band crossing the Fermi level and coexisti…
Pseudogap and Superconducting Fluctuations in High-Tc Cuprates
Shigeki Onoda, Masatoshi Imada
We analyze pseudogap phenomena widely observed in the underdoped cuprates. We assume the existence of a strong d-wave pairing force competing with antiferromagnetic(AFM) fluctuatio…
Theory of Electron Differentiation, Flat Dispersion and Pseudogap Phenomena
Masatoshi Imada, Shigeki Onoda
Aspects of electron critical differentiation are clarified in the proximity of the Mott insulator. The flattening of the quasiparticle dispersion appears around momenta and…
Quantum Effects in Resistance-Shunted Josephson Junctions
Takeo Kato, Masatoshi Imada
Thermodynamics and transport properties of resistance-shunted Josephson junctions are studied theoretically in the tight-binding limit E_C/E_J<<1, where E_C and E_J are a charging…
Control of Superconducting Correlations in High-Tc Cuprates
Hirokazu Tsunetsugu, Masatoshi Imada
A strategy to enhance d-wave superconducting correlations is proposed based on our numerical study for correlated electron models for high-Tc cuprates. We observe that the pairing…
Vortices and Quantum tunneling in Current-Biased 0-π-0 Josephson Junctions of d-wave Superconductors
Takeo Kato, Masatoshi Imada
We study a current-biased 0-π-0 Josephson junction made by high-T_c superconductors, theoretically. When a length of the πjunction is large enough, this junction contains a vortex-…