Digital holography for spatially resolved analysis of the semiconductor optical response.

We present spatially resolved measurements of the below-band-gap carrier-induced absorption and concurrent phase change in a semiconductor with the help of transmission digital holography. The application is demonstrated for a bulk GaAs sample, while the holograms are recorded with a conventional CMOS sensor. We show that the phase information enables spatially resolved monitoring of excess carrier distributions.

Monitoring of photochemically induced changes in phase-modulating samples with digital holographic microscopy.

This paper analyzes the performance of single-shot digital holographic microscopy for rapid characterization of static step-index structures in transparent polymer materials and for online monitoring of the photoinduced polymerization dynamics. The experiments are performed with a modified Mach-Zehnder transmission digital holographic microscope of high stability (phase accuracy of 0.69°) and of high magnification (of ≈90×).

Laser generation of shock waves in a water suspension with light-absorbing particles.

We report the generation of shock waves in a disperse medium with absorbing particles of black pigment in the water using continuous laser radiation. As a result of the experimental investigation it was found that the illuminating beam diameter growth at the constant laser power results in the decrease of the signals' modulation frequencies, improving their stability and increasing their amplitudes. In turn, the decrease of the signal's modulation frequency is caused by the growth of time, which is needed for heating the medium to the critical temperature of cavitation.