78 citations · 284 across the 17 of their papers we have counts for
18 papers
Time- and Frequency-Resolved Observation of Inverse Orbital Hall Effect in Gallium Nitride via Terahertz Polarimetry
Kota Aikyo, Tomohiro Fujimoto, Ami Mi Shirai +6
Orbitronics has attracted significant attention as a platform for information storage and processing that exploits the orbital angular momentum (OAM) of electrons without the need…
Large Photoelasticity in Topological Antiferromagnet MnSn Studied by Coherent Acoustic Phonon
Yuchen Wang, Takuya Matsuda, Yuta Murotani +5
We investigate the role of ultrafast strain on the electronic and optical responses in topological antiferromagnet MnSn thin films using near-infrared femtosecond pump-probe sp…
Signature of inverse orbital Hall effect in silicon studied using time-resolved terahertz polarimetry
Ami Mi Shirai, Kota Aikyo, Yuta Murotani +6
We investigated the anomalous Hall conductivity induced in silicon by circularly polarized light at room temperature using near-infrared (NIR) pump-terahertz (THz) probe spectrosco…
Correction of broadband terahertz electro-optic sampling with GaSe crystals
Kotaro Ogawa, Natsuki Kanda, Yuta Murotani +3
Gallium selenide (GaSe) is an efficient nonlinear crystal for electro-optic (EO) sampling in the multi-terahertz (THz) frequency range. However, the lattice resonance at several TH…
Calculations in Unified theory of the photovoltaic Hall effect by field- and light-induced Berry curvatures
Yuta Murotani, Tomohiro Fujimoto, Ryusuke Matsunaga
Photovoltaic Hall effect is an interesting platform of Berry curvature engineering by external fields. Floquet engineering aims at generation of light-induced Berry curvature assoc…
Unified theory of the photovoltaic Hall effect by field- and light-induced Berry curvatures
Yuta Murotani, Tomohiro Fujimoto, Ryusuke Matsunaga
Photovoltaic Hall effect, i.e., generation of a photocurrent perpendicular to the bias electric field, is an interesting platform of Berry curvature engineering by external fields.…
Valley polarization dynamics of photoinjected carriers at the band edge in room-temperature silicon studied by terahertz polarimetry
Ami M. Shirai, Yuta Murotani, Tomohiro Fujimoto +3
Sixfold-degenerate valleys in Si have attracted considerable attention for valleytronics application. Using optical pump-terahertz (THz) probe spectroscopy, we study the dynamics o…
Light-induced inverse spin Hall effect and field-induced circular photogalvanic effect in GaAs revealed by two-dimensional terahertz Fourier analysis
Tomohiro Fujimoto, Yuta Murotani, Tomohiro Tamaya +7
The electromotive force transverse to a bias field under irradiation of circularly polarized light, namely the photovoltaic Hall response or light-induced anomalous Hall effect, ha…
Programmable generation of counterrotating bicircular light pulses in the multi-terahertz frequency range
Kotaro Ogawa, Natsuki Kanda, Yuta Murotani +1
The manipulation of solid states using intense infrared or terahertz light fields is a pivotal area in contemporary ultrafast photonics research. While conventional circular polari…
Anomalous Hall transport by optically injected isospin degree of freedom in Dirac semimetal thin film
Yuta Murotani, Natsuki Kanda, Tomohiro Fujimoto +7
Chirality of massless fermions emergent in condensed matter is a key to understand their characteristic behavior as well as to exploit their functionality. However, chiral nature o…
Time-domain characterization of electric field vector in multi-terahertz pulses using polarization-modulated electro-optic sampling
Natsuki Kanda, Mayuri Nakagawa, Yuta Murotani +1
We demonstrated characterizing the electric field waveform of multi-terahertz pulses (10-50 THz) as vector quantities in the time domain by applying the polarization modulated elec…
Observation of Terahertz Spin Hall Conductivity Spectrum in GaAs with Optical Spin Injection
Tomohiro Fujimoto, Takayuki Kurihara, Yuta Murotani +7
We report the first observation of the spin Hall conductivity spectrum in GaAs at room temperature. Our terahertz polarimetry with a precision of several rads resolves the Farad…
Disentangling the Competing Mechanisms of Light-Induced Anomalous Hall Conductivity in Three-Dimensional Dirac Semimetal
Yuta Murotani, Natsuki Kanda, Tomohiro Fujimoto +7
We experimentally elucidate the origin of the anomalous Hall conductivity in a three-dimensional Dirac semimetal, CdAs, driven by circularly polarized light. Using time-res…
Stimulated Rayleigh Scattering Enhanced by a Longitudinal Plasma Mode in a Periodically Driven Dirac Semimetal CdAs
Yuta Murotani, Natsuki Kanda, Tatsuhiko N. Ikeda +6
Using broadband (12-45 THz) multi-terahertz spectroscopy, we show that stimulated Rayleigh scattering dominates the transient optical conductivity of cadmium arsenide, a Dirac semi…
Tracking ultrafast change of multiterahertz broadband response functions in a photoexcited Dirac semimetal CdAs thin film
Natsuki Kanda, Yuta Murotani, Takuya Matsuda +5
The electromagnetic response of Dirac semimetals in the infrared and terahertz frequency ranges is attracting growing interest for potential applications in optoelectronics and non…
Nonlinear optical response of collective modes in multiband superconductors assisted by nonmagnetic impurities
Yuta Murotani, Ryo Shimano
In multiband superconductors, multiple collective modes exist associated with the multiple order parameters. Oscillations of the amplitude and the relative phase of the order param…
Infrared activation of the Higgs mode by supercurrent injection in superconducting NbN
Sachiko Nakamura, Yudai Iida, Yuta Murotani +3
Higgs mode in superconductors, i.e. the collective amplitude mode of the order parameter does not associate with charge nor spin fluctuations, therefore it does not couple to the e…
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,…