Optical grating and THz polarizer based on normal grade single crystal diamond fast fabricated by fs laser

In this paper, we have researched the fs laser induced the phase transition in the normal grade single crystal diamond plates. The results show that the optical properties and electric properties of the irradiated region closely relate to the degree of the phase transition. We have succeeded in fabricating the optical gratings on the surface and inside of the diamond plates even though only partial material in the irradiated region phase-transforms from single crystal phase to amorphous phase. The gratings can be used as terahertz polarizers likewise. The modulation depths are 53% at 1.6 THz and 40% at 2.52 THz, which can be further improved by optimizing the fabrication parameters and the fill factors of gratings. We have also fabricated the electric wire on the surface of the normal grade diamond plate.