ABH damping of monolithic silica glass cantilever by structural and material modification using fs laser micromachining

摘要

Combining femtosecond laser exposure with chemical etching enables the fabrication of arbitrary 3D shapes in fused silica with micron precision. Here, we investigate the use of this process combined with additional tuning of the material properties for controlling the vibrational behavior of silica microcantilevers through an acoustic black hole (ABH) effect. This effect, caused by a tapered profile at the cantilever's end, enables the trapping of propagating acoustic waves. Such cantilevers with ABH design show a remarkable amplitude decrease in the resonance peak without adding any damping material as demonstrated experimentally. Finally, using Fourier-transform infrared spectroscopy (FTIR), we observe residual effects of the laser exposure at the surface of the specimen that have noticeable influence on the dynamic behavior of the device.