Design of a full-silica pulse-compression grating.

A diffraction grating engraved on a two-dimensional photonic crystal composed of square air holes in a silica matrix is numerically studied for the compression of ultrashort pulses. The silica is therefore the only solid material of the grating, and the reflection of the incident beam is based on the contrast of the air and silica refractive indices. This optical component enables the single use of silica as a solid material, presenting a high laser-induced damage threshold. In comparison to gratings engraved on a dielectric stack, multilayer dielectric, it offers the advantage of avoiding the presence of interfaces between two solid materials with different mechanical properties and sources of mechanical constraints that can distort the grating.