211 citations · 1.6k across the 37 of their papers we have counts for
26 papers · 1 filter
Quantum phase transition between hyperuniform density distributions
Shiro Sakai, Ryotaro Arita, Tomi Ohtsuki
We study an electron distribution under a quasiperiodic potential in light of hyperuniformity, aiming to establish a classification and analysis method for aperiodic but orderly de…
Hyperuniform electron distributions controlled by electron interactions in quasicrystal
Shiro Sakai, Ryotaro Arita, Tomi Ohtsuki
We study how the electron-electron interactions influence the charge distributions in the metallic state of quasicrystals. As a simple theoretical model, we introduce an extended H…
Doped Mott insulator on Penrose tiling
Shiro Sakai, Nayuta Takemori
We study the effect of carrier doping to the Mott insulator on the Penrose tiling, aiming at clarifying the interplay between quasiperiodicity and strong electron correlations. We…
Fermi surface expansion above critical temperature in a Hund ferromagnet
Yusuke Nomura, Shiro Sakai, Ryotaro Arita
Using a cluster extension of the dynamical mean-field theory, we show that strongly correlated metals subject to Hund's physics exhibit significant electronic structure modulations…
Natural orbital impurity solver for real-frequency properties at finite temperature
Motoharu Kitatani, Shiro Sakai, Ryotaro Arita
We extend the natural orbital impurity solver [PRB 90, 085102 (2014)] to finite temperatures and apply it to calculate spectral and transport properties of correlated electrons wit…
Fully filling-controlled pyrochlore ruthenates: emergent ferromagnetic-metal state and geometrical Hall effect
Ryoma Kaneko, Kentaro Ueda, Shiro Sakai +4
Carrier doping to the Mott insulator is essential to produce highly correlated metals with emergent properties. Pyrochlore ruthenates, PrRuO (Ru- electron num…
Effect of Electron-Electron Interactions on Metallic State in Quasicrystals
Shiro Sakai, Akihisa Koga
We theoretically study the effect of electron-electron interactions on the metallic state of quasicrystals. To address the problem, we introduce the extended Hubbard model on the A…
Direct Connection between Mott Insulator and d-Wave High-Temperature Superconductor Revealed by Continuous Evolution of Self-Energy Poles
Shiro Sakai, Marcello Civelli, Masatoshi Imada
The high-temperature superconductivity in copper oxides emerges when carriers are doped into the parent Mott insulator. This well-established fact has, however, eluded a microscopi…
Correlation-driven Lifshitz transition at the emergence of the pseudogap phase in the two-dimensional Hubbard model
Helena Braganca, Shiro Sakai, M. C. O. Aguiar +1
We study the relationship between the pseudogap and Fermi-surface topology in the two-dimensional Hubbard model by means of the cellular dynamical mean-field theory. We find two po…
Hidden-Fermion Representation of Self-energy in Pseudogap and Superconducting States of Two-Dimensional Hubbard Model
Shiro Sakai, Marcello Civelli, Masatoshi Imada
We study the frequency-dependent structure of electronic self-energy in the pseudogap and superconducting states of the two-dimensional Hubbard model. We present the self-energy ca…
Real-space renormalized dynamical mean field theory
Dai Kubota, Shiro Sakai, Masatoshi Imada
We propose real-space renormalized dynamical mean field theory (rr-DMFT) to deal with large clusters in the framework of a cluster extension of the DMFT. In the rr-DMFT, large clus…
Hidden fermionic excitation in the superconductivity of the strongly attractive Hubbard model
Shiro Sakai, Marcello Civelli, Yusuke Nomura +1
We scrutinize the real-frequency structure of the self-energy in the superconducting state of the attractive Hubbard model within the dynamical mean-field theory. Within the strong…
Evidence for hidden fermion that triggers high-temperature superconductivity in cuprates
Shiro Sakai, Marcello Civelli, Masatoshi Imada
In superconductors, electrons bound into Cooper pairs conduct a dissipationless current. The strength of the Cooper pairs scales with the value of the critical transition temperatu…
Nonlocal correlations induced by Hund's coupling: a cluster DMFT study
Yusuke Nomura, Shiro Sakai, Ryotaro Arita
We study spatial correlation effects in multiorbital systems, especially in a paramagnetic metallic state subject to Hund's coupling. We apply a cluster extension of the dynamical…
Multi-orbital cluster dynamical mean-field theory with an improved continuous-time quantum Monte Carlo algorithm
Yusuke Nomura, Shiro Sakai, Ryotaro Arita
We implement a multi-orbital cluster dynamical mean-field theory (DMFT), by improving a sample-update algorithm in the continuous-time quantum Monte Carlo method based on the inter…
Doping evolution of the electron-hole asymmetric s-wave pseudogap in underdoped high-Tc cuprate superconductors
Shiro Sakai, Marcello Civelli
We study the doping evolution of the electronic structure in the pseudogap state of high-Tc cuprate superconductors, by means of a cluster extension of the dynamical mean-field the…
Ab initio GW calculation for organic compounds (TMTSF)2PF6
Kazuma Nakamura, Shiro Sakai, Ryotaro Arita +1
We present an ab initio GW calculation to study dynamical effects on an organic compound (TMTSF)2PF6. Calculated polarized reflectivities reproduce experimental plasma edges at aro…
Exploring the Dark Side of Cuprate Superconductors: s-wave Symmetry of the Pseudogap
S. Sakai, S. Blanc, M. Civelli +12
We reveal the full energy-momentum structure of the pseudogap of underdoped high-Tc cuprate superconductors. Our combined theoretical and experimental analysis explains the spectra…
Effective Onsite Interaction for Dynamical Mean-Field Theory
Yusuke Nomura, Merzuk Kaltak, Kazuma Nakamura +7
A scheme to incorporate non-local polarizations into the dynamical mean-field theory (DMFT) and a tailor-made way to determine the effective interaction for the DMFT are systematic…
Cluster-size dependence in cellular dynamical mean-field theory
Shiro Sakai, Giorgio Sangiovanni, Marcello Civelli +3
We examine the cluster-size dependence of the cellular dynamical mean-field theory (CDMFT) applied to the two-dimensional Hubbard model. Employing the continuous-time quantum Monte…
Doped high-Tc cuprate superconductors elucidated in the light of zeros and poles of electronic Green's function
Shiro Sakai, Yukitoshi Motome, Masatoshi Imada
We study electronic structure of hole- and electron-doped Mott insulators in the two-dimensional Hubbard model to reach a unified picture for the normal state of cuprate high-Tc su…
Reply to Comment on "Evolution of electronic structure of doped Mott insulator - reconstruction of poles and zeros of Green's function" [arXiv:0904.0454] by P. Phillips
Shiro Sakai, Yukitoshi Motome, Masatoshi Imada
In a recent Comment [arXiv:0904.0454] on our Letter [Phys. Rev. Lett. 102, 056404 (2009); arXiv:0809:0950], Phillips criticizes one specific issue discussed in our paper, concernin…
Evolution of electronic structure of doped Mott insulators - reconstruction of poles and zeros of Green's function
Shiro Sakai, Yukitoshi Motome, Masatoshi Imada
We study evolution of metals from Mott insulators in the carrier-doped 2D Hubbard model using a cluster extension of the dynamical mean-field theory. While the conventional metal i…
Itinerant ferromagnetism in the multiorbital Hubbard model: a dynamical mean-field study
Shiro Sakai, Ryotaro Arita, Hideo Aoki
In order to resolve the long-standing issue of how the itinerant ferromagnetism is affected by the lattice structure and Hund's coupling, we have compared various three-dimensional…