Near-field optical properties of multilayer ridge metal/multilayer-dielectric gratings for pulse compressor

摘要

The multilayer ridge metal/multilayer-dielectric gratings (MMDGs) for pulse compressors show high efficiency, broad bandwidths, large fabrication tolerances and high laser-induced damage thresholds. The diffraction efficiency, bandwidth, and near-field distribution of the multilayer structure ridge MMDG are theoretically investigated. Simulation results show that the film structure of the grating ridge has a great influence on the bandwidth and near-field distribution. The maximum electric field is located in the high-index layer of the grating ridge with high -1st diffraction efficiency. As the thickness of the high-index layer decreases, the maximum electric field moves to the low-index layer of the grating ridge with. Base on the results, the sandwich ridge MMDG is an ideal pulse compression grating for chirped pulse amplification systems.