774 citations · 3.8k across the 47 of their papers we have counts for
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Tachyonic and Plasma Instabilities of -Pairing States Coupled to Electromagnetic Fields
Naoto Tsuji, Masaya Nakagawa, Masahito Ueda
Cooper pairs featuring a nonzero center-of-mass crystal momentum and an off-diagonal long-range order (-pairing states) constitute exact eigenstat…
Higgs-mode resonance in third harmonic generation in NbN superconductors: multiband electron-phonon coupling, impurity scattering, and polarization-angle dependence
Naoto Tsuji, Yusuke Nomura
We theoretically investigate the resonance of third harmonic generation (THG) that has been observed at frequency being half of the superconducting gap in a multiband disordered su…
Higgs Mode in Superconductors
Ryo Shimano, Naoto Tsuji
When a continuous symmetry of a physical system is spontaneously broken, two types of collective modes typically emerge: the amplitude and phase modes of the order-parameter fluctu…
Nature of superconducting fluctuation in photo-excited systems
Ryuta Iwazaki, Naoto Tsuji, Shintaro Hoshino
The photo-excited state associated with superconducting fluctuation above the superconducting critical temperature is studied based on the time-dependent Ginzburg-Laundau app…
SO(4) FLEX+DMFT formalism with SU(2)SU(2)-symmetric impurity solver for superconductivity in the repulsive Hubbard model
Sharareh Sayyad, Naoto Tsuji, Massimo Capone +1
Here we have developed a FLEX+DMFT formalism, where the symmetry properties of the system are incorporated by constructing a SO(4) generalization of the conventional fluctuation-ex…
Higgs mode in the d-wave superconductor Bi2Sr2CaCu2O8+x driven by an intense terahertz pulse
Kota Katsumi, Naoto Tsuji, Yuki I. Hamada +7
We investigated the terahertz (THz)-pulse driven nonlinear response in the d-wave cuprate superconductor Bi2Sr2CaCu2O8+x (Bi2212) using a THz pump near-infrared probe scheme in the…
Polarization-resolved terahertz third-harmonic generation in a superconductor NbN: dominance of Higgs mode beyond the BCS approximation
Ryusuke Matsunaga, Naoto Tsuji, Kazumasa Makise +3
Recent advances in time-domain terahertz (THz) spectroscopy have unveiled that resonantly-enhanced strong THz third-harmonic generation (THG) mediated by the collective Higgs ampli…
Nonequilibrium steady states and transient dynamics of conventional superconductors under phonon driving
Yuta Murakami, Naoto Tsuji, Martin Eckstein +1
We perform a systematic analysis of the influence of phonon driving on the superconducting Holstein model coupled to heat baths by studying both the transient dynamics and the none…
Interplay of Pomeranchuk instability and superconductivity in the two-dimensional repulsive Hubbard model
Motoharu Kitatani, Naoto Tsuji, Hideo Aoki
Interplay of Pomeranchuk instability (spontaneous symmetry breaking of the Fermi surface) and d-wave superconductivity is studied for the repulsive Hubbard model on the square latt…
Nonlinear light-Higgs coupling in superconductors beyond BCS: Effects of the retarded phonon-mediated interaction
Naoto Tsuji, Yuta Murakami, Hideo Aoki
We study the contribution of the Higgs amplitude mode on the nonlinear optical response of superconductors beyond the BCS approximation by taking into account the retardation effec…
Damping of the Collective Amplitude Mode in Superconductors with Strong Electron-Phonon Coupling
Y. Murakami, P. Werner, N. Tsuji +1
We study the effect of strong electron-phonon interactions on the damping of the Higgs amplitude mode in superconductors by means of non-equilibrium dynamical mean-field simulation…
Multiple amplitude modes in strongly-coupled phonon-mediated superconductors
Yuta Murakami, Philipp Werner, Naoto Tsuji +1
We study collective amplitude modes of the superconducting order parameter in strongly-coupled electron-phonon systems described by the Holstein model using the nonequilibrium dyna…
Theory of light-induced resonances with collective Higgs and Leggett modes in multiband superconductors
Yuta Murotani, Naoto Tsuji, Hideo Aoki
We theoretically investigate coherent optical excitations of collective modes in two-band BCS superconductors, which accommodate two Higgs modes and one Leggett mode corresponding,…
FLEX+DMFT approach to the -wave superconducting phase diagram of the two-dimensional Hubbard model
Motoharu Kitatani, Naoto Tsuji, Hideo Aoki
The dynamical mean-field theory (DMFT) combined with the fluctuation exchange (FLEX) method, namely FLEX+DMFT, is an approach for correlated electron systems to incorporate both lo…
Theory of Anderson pseudospin resonance with Higgs mode in superconductors
Naoto Tsuji, Hideo Aoki
A superconductor illuminated by an ac electric field with frequency is theoretically found to generate a collective precession of Anderson's pseudospins, and hence a coherent a…