Iakushev S. Multilayer microstructures for dispersion compensation in ultrafast lasers

Object of research: multilayer dispersive microstructures providing negative dispersion. Aim: solving a problem which implies finding of physical regularities in experimentally observed ultrashort laser pulse compression in time domain with chirped mirrors. Results, novelty: For the first time theoretically described ultrashort pulse compression in time domain with chirped mirror taking into account a preliminary chirp due to dispersive effects. For the first time are found regularities in ultrashort pulse compression in time domain with single chirped mirror depending on the number of layers, it allowed to reveal a physics of pulse compression with chirped mirror when the layers number increased. For the first time was comprehensively investigated the influence on the pulse profile such negative factors as phase ripples, third order dispersion, insufficient chirped mirror's bandwidth, it are found the conditions of transform-limited pulse producing. For the first time are found regularities in ultrashort pulse compression with pair of chirped mirrors depending on the number of layers, incident angle and polarization type. For the first time was theoretically proved the usage of silicon nitride with air gapes in the chirped mirrors, it provides high refractive index contrast and makes possible the synthesis of chirped mirrors with broad bandwidth. For the first time was theoretically proved the usage of Bragg wavelength modulation for the group delay dispersion oscillations shifting for the purpose of synthesis of complementary chirped mirrors. Application field: optics, laser physics.