124 citations · 386 across the 31 of their papers we have counts for
32 papers
Nonreciprocal phonon propagation via spatially asymmetric magnon-phonon coupling
Hiroyuki Moriya, Motoki Asano, Daiki Hatanaka +3
Nonreciprocal propagation of surface acoustic waves (SAWs) based on the spatial asymmetry of magnon-phonon coupling is demonstrated. This nonreciprocity is enabled by an acoustic w…
Interpretable self-driving sputter epitaxy: from black-box optimization to human-usable growth rules
Yuki K. Wakabayashi, Yui Ogawa, Franz Benedict Romero +2
Self-driving laboratories have emerged as powerful tools for navigating high-dimensional process spaces, yet systems remain black-box optimizers that yield limited transferable pro…
Intrinsic low-spin state and strain-tunable anomalous Hall scaling in high-quality SrRuO3 (111) films
Harunori Shiratani, Yuki K. Wakabayashi, Yoshiharu Krockenberger +6
The (111)-oriented 4d ferromagnetic perovskite SrRuO3 (SRO) offers a unique triangular-lattice geometry, making it a promising platform for exploring Berry-curvature-driven and spi…
Physics-informed acquisition weighting for stoichiometry-constrained Bayesian optimization of oxide thin-film growth
Yuki K. Wakabayashi, Takuma Otsuka, Yoshiharu Krockenberger +1
We present a physics-informed Bayesian optimization (PIBO) with a concise modification to its acquisition function to incorporate the physical prior knowledge. Specifically, this m…
On-chip magnon polaron generation in mode-matched cavity magnomechanics
Daiki Hatanaka, Motoki Asano, Megumi Kurosu +3
Generation of magnon polarons, which are hybridized states resulting from strong magnon-phonon coupling, is a key to enabling coherent manipulation in acoustic and spintronic devic…
Orbital-resolved anisotropic electron pockets in electron-doped SrTiO3 observed by ARPES
Yuki K. Wakabayashi, Akihira Munakata, Yoshitaka Taniyasu +1
SrTiO3 has attracted considerable interest as a wide-band gap semiconductor for advanced high-k capacitors and photocatalytic applications. Although previous angle-resolved photoem…
Electronic transport properties of titanium nitride grown by molecular beam epitaxy
Kosuke Takiguchi, Yoshiharu Krockenberger, Tom Ichibha +4
This study investigates the molecular beam epitaxial (MBE) growth of titanium nitride (TiN) thin films, achieving a high residual resistivity ratio (RRR) of 15.8. We observed a str…
Single monolayer ferromagnetic perovskite SrRuO3 with high conductivity and strong ferromagnetism
Yuki K. Wakabayashi, Masaki Kobayashi, Yoshiharu Krockenberger +4
Achieving robust ferromagnetism and high conductivity in atomically thin oxide materials is critical for advancing spintronic technologies. Here, we report the growth of a highly c…
Single-layer spin-orbit-torque magnetization switching due to spin Berry curvature generated by minute spontaneous atomic displacement in a Weyl oxide
Hiroto Horiuchi, Yasufumi Araki, Yuki K. Wakabayashi +8
Spin Berry curvature characterizes the band topology as the spin counterpart of Berry curvature and is crucial in generating novel spintronics functionalities. By breaking the crys…
Role of Ion Milling Angle in Determining Conducting and Insulating States on SrTiO3 Surfaces
Yuki K. Wakabayashia, Yoshiharu Krockenberger, Kosuke Takiguchi +2
SrTiO3 (STO), a promising wide-bandgap semiconductor for high-k capacitors and photocatalysis, requires precise surface control for device fabrication. This study investigates the…
Influence of Ru composition deviation from stoichiometry on intrinsic spin-to-charge conversion in SrRuO3
Shingo Kaneta-Takada, Yuki K. Wakabayashi, Hikari Shinya +5
Interconversion between charge and spin currents is a key phenomenon in realizing next-generation spintronic devices. Highly efficient spin-charge interconversion is expected to oc…
Correlated Ligand Electrons in the Transition-Metal Oxide SrRuO
Yuichi Seki, Yuki K. Wakabayashi, Takahito Takeda +9
In transition-metal compounds, the transition-metal d electrons play an important role in their physical properties; however, the effects of the electron correlation between the li…
SrRuO3 under tensile strain: Thickness-dependent electronic and magnetic properties
Yuki K. Wakabayashi, Masaki Kobayashi, Yuichi Seki +6
The burgeoning fields of spintronics and topological electronics require materials possessing a unique combination of properties: ferromagnetism, metallicity, and chemical stabilit…
Berezinskii-Kosterlitz-Thouless transition in rhenium nitride films
Kosuke Takiguchi, Yoshiharu Krockenberger, Yoshitaka Taniyasu +1
The quest to manipulate and understand superconductivity demands exploring diverse materials and unconventional behaviors. Here, we investigate the BKT transition in synthesized Re…
Reduction of Interlayer Interaction in Multilayer Stacking Graphene with Carbon Nanotube Insertion: Insights from Experiment and Simulation
Mingda Ding, Taiki Inoue, John Isaac Enriquez +6
The creation of multilayer graphene (Gr), while preserving the brilliant properties of monolayer Gr derived from its unique band structure, can expand the application field of Gr t…
Magnetic anisotropy driven by ligand in 4d transition metal oxide SrRuO3
Yuki K. Wakabayashi, Masaki Kobayashi, Yuichi Seki +7
The origin of magnetic anisotropy in magnetic compounds is a longstanding issue in solid state physics and nonmagnetic ligand ions are considered to contribute little to magnetic a…
Stoichiometric growth of SrTiO3 films via Bayesian optimization with adaptive prior mean
Yuki K. Wakabayashi, Takuma Otsuka, Yoshiharu Krockenberger +3
Perovskite insulator SrTiO3 is expected to be applied to the next generation of electronic and photonic devices as high-k capacitors and photocatalysts. However, reproducible growt…
Scattering-dependent transport of SrRuO3 films: From Weyl fermion transport to hump-like Hall effect anomaly
Shingo Kaneta-Takada, Yuki K. Wakabayashi, Yoshiharu Krockenberger +5
Recent observation of quantum transport phenomena of Weyl fermions has brought much attention to 4d ferromagnetic perovskite SrRuO3 as a magnetic Weyl semimetal. Besides, the hump-…
Observation of Acoustically Induced Dressed States of Rare-Earth Ions
Ryuichi Ohta, Gregoire Lelu, Xuejun Xu +9
Acoustically induced dressed states of long-lived erbium ions in a crystal are demonstrated. These states are formed by rapid modulation of two-level systems via strain induced by…
Impedance-matched High-overtone Bulk Acoustic Resonator
Megumi Kurosu, Daiki Hatanaka, Ryuichi Ohta +3
A high-overtone bulk acoustic resonator (HBAR), in which a piezoelectric transducer is set on an acoustic cavity, has been attracting attention in both fundamental research and RF…
Isotropic orbital magnetic moments in magnetically anisotropic SrRuO3 films
Yuki K. Wakabayashi, Masaki Kobayashi, Yukiharu Takeda +6
Epitaxially strained SrRuO3 films have been a model system for understanding the magnetic anisotropy in metallic oxides. In this paper, we investigate the anisotropy of the Ru 4d a…
Bayesian optimization with experimental failure for high-throughput materials growth
Yuki K. Wakabayashi, Takuma Otsuka, Yoshiharu Krockenberger +3
A crucial problem in achieving innovative high-throughput materials growth with machine learning and automation techniques, such as Bayesian optimization (BO) and robotic experimen…
Superconductivity in infinite-layer CaCuO2-brownmillerite Ca2Fe2O5 superlattices
Ai Ikeda, Yoshiharu Krockenberger, Yoshitaka Taniyasu +1
High-temperature cuprate superconductors have naturally a superlattice structure. Infinite-layer CaCuO2 is the common ingredient of cuprates with superconducting transition tempera…
Single-domain perpendicular magnetization induced by the coherent O 2p-Ru 4d hybridized state in an ultra-high-quality SrRuO3 film
Yuki K. Wakabayashi, Masaki Kobayashi, Yukiharu Takeda +8
We investigated the Ru 4d and O 2p electronic structure and magnetic properties of an ultra-high-quality SrRuO3 film on SrTiO3 grown by machine-learning-assisted molecular beam epi…