13 citations · 31 across the 8 of their papers we have counts for
4 papers · 1 filter
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…