Abstract

Recently, diamond has attracted great interest as a platform for quantum information, because it has nitrogen vacancy (NV) centers, which can be exploited as quantum bits, since the electron spin at the NV center has a long coherence time and be controlled with light [1]. Therefore, the precise three-dimensional fabrication inside diamond is a great challenge for realization of integrated diamond-based quantum devices. One of the key components in diamond-based quantum devices is an optical waveguide, which can be written by fs laser direct writing. Previously, we found that a single-pulse irradiation with 100-300 fs laser pulses cannot induce any permanent modification inside diamond, but double-pulse irradiation with 200-400 fs laser pulses was effective to induce larger permanent modification [2]. However, the difference in the dynamics after fs laser irradiation between single- and double-pulse irradiation has remained unclear. In this study, we observed stress dynamics using a time-resolved interferometer to investigate the difference between single- and double-pulse irradiation.

© 2016 Japan Society of Applied Physics, Optical Society of America