Redeposition-Free Deep Etching in Small KY(WO) Samples.

KY(WO) is a promising material for on-chip laser sources. Deep etching of small KY(WO) samples in combination with various thin film deposition techniques is desirable for the manufacturing of such devices. There are, however, several difficulties that need to be overcome before deep etching of KY(WO) can be realized in small samples in a reproducible manner.

Imaging local acoustic pressure in microchannels.

A method for determining the spatially resolved acoustic field inside a water-filled microchannel is presented. The acoustic field, both amplitude and phase, is determined by measuring the change of the index of refraction of the water due to local pressure using stroboscopic illumination. Pressure distributions are measured for the fundamental pressure resonance in the water and two higher harmonic modes.