Tsuguo Sawada

TL;DR: The photothermal effect of an ultratrace amount of nonfluorescent molecules in liquid was determined by optimizing the optical arrangement for a thermal lens microscope and the relation between molecular behavior in the probing volume and the signal was discussed.

TL;DR: Gigahertz surface acoustic waves have been optically generated and detected on aluminum metallic films and silicon wafers using the laser-induced grating technique as mentioned in this paper, and the acoustic velocities were in good agreement with those of Rayleigh waves.

Abstract: Ultrafast transient reflecting grating (TRG) spectroscopy was applied to investigate the influence of various defect states on ultrafast carrier dynamics of up to 3 ps duration in an ion-implanted silicon surface region. The TRG spectra revealed the energy-state distribution of two kinds of defect states, and it was observed that photoexcited carriers were trapped in each state depending on annealing time. It was proposed that TRG spectroscopy can be used as an analytical method for characterizing defects in the surface region of semicondcutors.

TL;DR: In this paper, an enhanced technique of heterodyne detection for transient grating experiments has been developed, which features a very simple optical alignment because no lenses are used to focus beams on the samples.

TL;DR: Sound waves emitted from cells of Bacillus subtilis at frequencies between 8 and 43 kHz with broad peaks at approximately 8.5, 19, 29, and 37 kHz suggest that the detected sound waves function as a growth-regulatory signal between cells.