13 citations · 31 across the 8 of their papers we have counts for
8 papers
In situ estimation of local acoustic pressure amplitude by force balancing with a ferrofluid droplet probe
Seiya Usui, Yoshiaki Uchida, Akira Nagakubo +1
Acoustic tweezers enable non-contact manipulation of microscale objects, but quantitative in situ evaluation of the peak local pressure amplitude remains difficult in confined devi…
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…
Suppression of Brillouin oscillation in transparent free-standing diamond thin films in picosecond ultrasound
Hsu Kai Weng, Akira Nagakubo, Hideyuki Watanabe +1
Brillouin oscillation appears in picosecond ultrasonics for a transparent specimen because of backward light scattering by moving strain pulse. Its amplitude is comparable with tho…
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…
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…
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…