13 citations · 54 across the 14 of their papers we have counts for
15 papers
Simultaneous Recovery of Dielectric Constants, Photoelastic Constants, and Strain Profiles from Picosecond Ultrasonic Echoes
Richard Wiltshaw, Motonobu Tomoda, Osamu Matsuda +3
Light reflected from a deforming solid depends on boundary motion and strain-induced modulation of the dielectric response. For a propagating acoustic field, scattering from differ…
Tracer-free Contactless Acoustic Microrheometry Quantifies Viscoelastic Spectrum of Phase-separated Condensates
Kichitaro Nakajima, Taichi Yoshikawa, Yuta Suzuki +13
The rheology of phase-separated condensates plays a central role in applications spanning advanced materials design and cellular processes, yet quantitative characterization of the…
Exploration of the potential energy surface for the conformational interconversion of the amyloid peptide at the fibril end
Yasuhiro Oishi, Motoharu Kitatani, Kichitaro Nakajima +2
The formation of amyloid fibrils comprising amyloid (A) peptides is associated with the pathology of Alzheimer's disease. In this study, we theoretically investigated the A$…
Determination of the electron trap level in Fe-doped GaN by phonon-assisted conduction phenomenon
Hiroki Fukuda, Akira Nagakubo, Shigeyoshi Usami +6
We acoustically measured the energy level for thermally activated conduction (TAC) in high-resistivity Fe-doped GaN using the non-contacting antenna-transmission acoustic-resonance…
Theoretical Analysis on the Stability of 1-Pyrenebutanoic Acid Succinimidyl Ester Adsorbed on Graphene
Yasuhiro Oishi, Hirotsugu Ogi, Satoshi Hagiwara +2
The adsorbed structure of 1-pyrenebutanoic acid succinimidyl ester (PASE) on graphene was investigated based on density functional theory. We found two locally stable structures: a…
Restructuring in bimetallic core-shell nanoparticles: Real time observation
Nobutomo Nakamura, Koji Matsuura, Akio Ishii +1
The formation process of core-shell bimetallic nanoparticles synthesized by sputtering onto a substrate is observed in real time using an originally developed acoustic technique. T…
The angular dependence of magnetization dynamics induced by a GHz range strain pulse
Kakeru Tojo, Akira Nagakubo, Hirotsugu Ogi
The dynamics of magnetization is important in spintronics, where the coupling between phonon and magnon attracts much attention. In this work, we study the angular dependence of th…
Elastic constant of dielectric nano-thin films using three-layer resonance studied by picosecond ultrasonics
Hiroki Fukuda, Akira Nagakubo, Hirotsugu Ogi
Elastic constants and sound velocities of nm-order thin films are essential for designing acoustic filters. However, it is difficult to measure them for dielectric thin films. In t…
Lattice thermal conductivity in isotope diamond asymmetric superlattices
Hsu Kai Weng, Akira Nagakubo, Hideyuki Watanabe +1
We study lattice thermal conductivity of isotope diamond superlattices consisting of 12C and 13C diamond layers at various superlattice periods. It is found that the thermal conduc…
Ultrahigh-Frequency Wireless MEMS QCM Biosensor for Direct Label-Free Detection of Biomarkers in a Large Amount of Contaminants
Kentaro Noi, Arihiro Iwata, Fumihito Kato +1
Label-free biosensors, including conventional quartz-crystal-microbalance (QCM) biosensor, are seriously affected by nonspecific adsorption of contaminants involved in analyte solu…
Sensitive label-free IgG detection using MEMS QCM biosensor with 125-MHz wireless quartz resonator
Lianjie Zhou, Fumihito Kato, Hirotsugu Ogi
We present a wireless QCM biosensor fabricated using MEMS technology. The MEMS QCM biosensor contains a 125-MHz AT-cut quartz resonator embedded in the microchannel. Because of the…
Effect of interfacial damping on high-frequency surface wave resonance on a nanostrip-bonded substrate
Wenlou Yuan, Akira Nagakubo, Hirotsugu Ogi
Since surface acoustic waves (SAW) are often generated on substrates to which nanostrips are periodically attached, it is very important to consider the effect of interface between…
Acceleration of amyloid fibril formation by multichannel sonochemical reactor
Kentaro Noi, Kichitaro Nakajima, Keiichi Yamaguchi +5
Formation of amyloid fibrils of various amyloidogenic proteins is dramatically enhanced by ultrasound irradiation. For applying this phenomenon to the study of protein aggregation…
Interplanar stiffness in defect-free monocrystalline graphite
Koichi Kusakabe, Atsuki Wake, Akira Nagakubo +4
The interplanar bond strength in graphite has been identified to be very low owing to the contribution of the van der Waals interaction. However, in this study, we use microscopic…
Perturbation theories behind thermal mode spectroscopy for high-accuracy measurement of thermal diffusivity of solids
Hideshi Ishida, Hirotsugu Ogi
Thermal mode spectroscopy (TMS) has been recently proposed for accurately measuring thermal diffusivity of solids from a temperature decay rate of a specific thermal mode selected…