157 citations · 1.9k across the 60 of their papers we have counts for
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Generalized Keldysh formalism for nonequilibrium correlation functions and its application to fluctuation dynamics
Ken Inayoshi, Hiroshi Shinaoka, Yuta Murakami
Recent advances in time-resolved spectroscopies provide increasing access to collective dynamics in correlated quantum materials. However, computing the corresponding nonequilibriu…
Many-body effects on high-harmonic generation in Hubbard ladders
Yuta Murakami, Thomas Hansen, Shintaro Takayoshi +2
We show how many-body effects associated with background spin dynamics control the high-harmonic generation (HHG) in Mott insulators by analyzing the two-leg ladder Hubbard model.…
Photo-induced nonequilibrium states in Mott insulators
Yuta Murakami, Denis Golež, Martin Eckstein +1
The study of nonequilibrium phenomena in interacting lattice systems can provide new perspectives on correlation effects, and information on metastable states of matter. Mott insul…
Exciton-spin interactions in antiferromagnetic charge-transfer insulators
Tatsuya Kaneko, Yuta Murakami, Denis Golež +2
We derive exciton-spin interactions from a microscopic correlated model that captures important aspects of the physics of charge-transfer (CT) insulators to address magnetism assoc…
Energy flow during relaxation in an electron-phonon system with multiple modes: A nonequilibrium Green's function study
Ken Inayoshi, Akihisa Koga, Yuta Murakami
We investigate an energy flow in an extended Holstein model describing electron systems coupled to hot-phonons and heat-bath phonons. To analyze the relaxation process after the ph…
Non-thermal superconductivity in photo-doped multi-orbital Hubbard systems
Sujay Ray, Yuta Murakami, Philipp Werner
Superconductivity in laser-excited correlated electron systems has attracted considerable interest due to reports of light-induced superconducting-like states. Here we explore the…
Majorana Gap Formation in the Anisotropic Kitaev Model with Ordered Flux Configuration
Akihiro Hashimoto, Yuta Murakami, Akihisa Koga
We study the Kitaev model with direction dependent interactions to investigate how the flux configuration and/or the anisotropy in the exchanges affect the Majorana excitations. Sy…
Spin, charge and -spin separation in one-dimensional photo-doped Mott insulators
Yuta Murakami, Shintaro Takayoshi, Tatsuya Kaneko +2
We show that effectively cold metastable states in one-dimensional photo-doped Mott insulators described by the extended Hubbard model exhibit spin, charge and -spin separation.…
Efficient Scheme for Time-dependent Thermal Pure Quantum State: Application to the Kitaev Model with Armchair Edges
H. Taguchi, A. Koga, Y. Murakami
We consider the time-dependent thermal pure quantum state method and introduce the efficient scheme to evaluate the change in physical quantities induced by the time-dependent pert…
Multiscale space-time ansatz for correlation functions of quantum systems based on quantics tensor trains
Hiroshi Shinaoka, Markus Wallerberger, Yuta Murakami +4
Correlation functions of quantum systems -- central objects in quantum field theories -- are defined in high-dimensional space-time domains. Their numerical treatment thus suffers…
Scattering phenomena for spin transport in Kitaev spin liquid
Joji Nasu, Yuta Murakami, Akihisa Koga
The Kitaev model exhibits a canonical quantum spin liquid as a ground state and hosts two fractional quasiparticles, itinerant Majorana fermion and localized flux excitation. The f…
Second-order magnetic responses in quantum magnets: Magnetization under ac magnetic fields
Tatsuya Kaneko, Yuta Murakami, Shintaro Takayoshi +1
We investigate second-order magnetic responses of quantum magnets against ac magnetic fields. We focus on the case where the component of the spin is conserved in the unperturb…
Anomalous temperature dependence of high-harmonic generation in Mott insulators
Yuta Murakami, Kento Uchida, Akihisa Koga +2
We reveal the crucial effect of strong spin-charge coupling on high-harmonic generation (HHG) in Mott insulators. In a system with antiferromagnetic correlations, the HHG signal is…
Thermally enhanced Majorana-mediated spin transport in the Kitaev model
Hirokazu Taguchi, Yuta Murakami, Akihisa Koga
We study how stable the Majorana-mediated spin transport in a quantum spin Kitaev model is against thermal fluctuations. Using the time-dependent thermal pure quantum state method,…
Photoinduced Phase Transition in Two-Band model on Penrose Tiling
Ken Inayoshi, Yuta Murakami, Akihisa Koga
We study the effects of the photo irradiation on the band insulating state in the two-band Hubbard model on the Penrose tiling. Examining the time- and site-dependent physical quan…
Unveiling the underlying interactions in Ta2NiSe5 from photo-induced lifetime change
Denis Golez, Sydney K. Y. Dufresne, Min-Jae Kim +14
We present a generic procedure for quantifying the interplay of electronic and lattice degrees of freedom in photo-doped insulators through a comparative analysis of theoretical ma…
Photo-induced Dynamics of Quasicrystalline Excitonic Insulator
Ken Inayoshi, Yuta Murakami, Akihisa Koga
We study the photo-induced dynamics of the excitonic insulator in the two-band Hubbard model on the Penrose tiling by means of the time-dependent real-space mean-field approximatio…
Light-induced hidden odd-frequency order in a model for AC
Philipp Werner, Yuta Murakami
Laser driving in systems with competing or coupled electronic orders can lead to the enhancement of orders, or even to the appearance of hidden phases without an equilibrium analog…
Role of Majorana fermions in spin transport of anisotropic Kitaev model
Hirokazu Taguchi, Yuta Murakami, Akihisa Koga +1
We study a quantum spin Kitaev model with zigzag edges to clarify the effects of anisotropy in the exchange couplings on the spin propagation. We simulate the spin and Majorana dyn…
Exploring nonequilibrium phases of photo-doped Mott insulators with Generalized Gibbs ensembles
Yuta Murakami, Shintaro Takayoshi, Tatsuya Kaneko +4
Photo-excited strongly correlated systems can exhibit intriguing non-thermal phases, but the theoretical investigation of them poses significant challenges. In this work, we introd…
Majorana correlations in the Kitaev model with ordered-flux structures
Akihisa Koga, Yuta Murakami, Joji Nasu
We study the effects of the flux configurations on the emergent Majorana fermions in the Kitaev model on a honeycomb lattice, where quantum spins are fractionalized into it…
Photo-induced phase transition and associated time scales in the excitonic insulator TaNiSe
Tanusree Saha, Denis Golez, Giovanni De Ninno +5
We investigate the non-equilibrium electronic structure and characteristic time scales in a candidate excitonic insulator, TaNiSe, using time- and angle-resolved photoemiss…
Bulk Photovoltaic Effect Driven by Collective Excitations in a Correlated Insulator
Tatsuya Kaneko, Zhiyuan Sun, Yuta Murakami +2
We investigate the bulk photovoltaic effect, which rectifies light into electric current, in a collective quantum state with correlation driven electronic ferroelectricity. We show…
High-harmonic generation in one-dimensional Mott insulator
Yuta Murakami, Shintaro Takayoshi, Akihisa Koga +1
We study high-harmonic generation (HHG) in the one-dimensional Hubbard model in order to understand its relation to elementary excitations as well as the similarities and differenc…