Mixed metal dielectric gratings for pulse compression

Abstract

We report on manufacturing and testing results of high efficiency mixed metal dielectric gratings (MMLD) for high power pulse compression applications. The gratings with 1780 l/mm are etched in the top low index layer of a Au-(SiO2/HfO2)4-SiO2 mirror stack. Various grating profiles manufactured in order to modify the near electric field distribution are damage tested on a facility operating at 1.053 µm, 500 fs pulse duration. We evidence that damage threshold is governed by the value of the maximum electric field intensity inside the grating pillar. Moreover thresholds close to 3 J/cm² beam normal are obtained with this new MMLD grating being thus an interesting alternative to gold and pure dielectric gratings for pulse compression applications.

Recent progress in the development of pulse compression gratings

“…Moreover such a design is also of interest in the context of large spectral bandwidth. While testing these MMLD gratings, we also observed a LID proportional to 1/|E| 2 [11,12]. These two results are summarized on Fig.…”

Femtosecond laser induced damage characterization of transmission volume phase gratings

“…A laser induceddamage threshold (LIDT) characterization of gratings, i.e., the highest fluence value for which no damage is produced, is a main task to determine its applicability range. In the last years, LIDT in reflection multilayer dielectric gratings [1][2][3] and in mixed metal dielectric gratings 4 has been investigated by varying the material composition of the multilayer and by proving different grating profiles. The damage dynamics were established for a wide class of gratings, but only in the reflection geometry.…”

“…For instance, damage at peak intensities due to interference effects has also been demonstrated in reflection gratings. [1][2][3][4] This damage mechanism is the main limitation on damage threshold for transmission gratings and for reflection gratings as well. Furthermore, the probabilistic model for Bragg incidence is determined substituting Eqs.…”

High-efficiency, broad-bandwidth metal/multilayer-dielectric gratings

“…However, MDGs cannot fulfill the broader bandwidth specifications [7]. Metal/multilayer-dielectric grating (MMDG) [8] with high diffraction efficiency and wide bandwidth [9,10] is a viable candidate for the realization of a broadband pulse compression grating (PCG) [11,12]. The grating ridge of the most reported MMDG design is rectangular, but rectangular grating ridge fabrication is difficult.…”