The role of chirp on the light-matter interaction of femto- and pico-second laser pulses with functional structured surfaces is studied using drag-reducing riblets as an example. The three-dimensional, periodic micros...The role of chirp on the light-matter interaction of femto- and pico-second laser pulses with functional structured surfaces is studied using drag-reducing riblets as an example. The three-dimensional, periodic microstructure naturally gives rise to a mutual interplay of （i） reflection, （ii） scattering, and （iii） diffraction phenomena of incident coherent light. Furthermore, for femtosecond pulses, the structure induces （iv） an optical delay equivalent to a consecutive temporal delay of 230 fs in places of the pulse. These features enable studying experimentally and numerically the effect of tuning both pulse duration τ and spectral bandwidth Δω on the features of the wideangle scattering pattern from the riblet structure. As a result, we discovered a significant breakdown of fringes in the scattering pattern with decreasing pulse duration and/or increasing spectral bandwidth. This unique type of chirp control is straightforward/y explained and verified by numerical modeling considering the spectral and temporal interaction between different segments within the scattered, linearly chirped pulse and the particular geometric features of the riblet structure. The visibility of the fringe pattern can be precisely adjusted, and the offstate is achieved using τ 〈 230 fs or Δω〉 2.85 × 10^13 rad/s.展开更多
The implementation of photoinduced linkage isomerism in molecular-based optical materials represents a promising approach for the synthesis of high-contrast,high-resolution photosensitive materials that are necessary...The implementation of photoinduced linkage isomerism in molecular-based optical materials represents a promising approach for the synthesis of high-contrast,high-resolution photosensitive materials that are necessary for high-density(holographic)data storage and/or real-three-dimensional(holographic)displays.The unsolved task of embedding a photofunctional coordination complex into a matrix like polymer polydimethylsiloxane(PDMS)with photoinduced isomerism of a SO-bond in the sulfoxide compoundRubpy2OSOPF6 is addressed.This approach allows to preserve the spectral properties within the solid dielectric environment,with an impact of PDMS on population and relaxation dynamics.All data are discussed in the framework of photofunctionality,storage,and display applications.展开更多
文摘The role of chirp on the light-matter interaction of femto- and pico-second laser pulses with functional structured surfaces is studied using drag-reducing riblets as an example. The three-dimensional, periodic microstructure naturally gives rise to a mutual interplay of （i） reflection, （ii） scattering, and （iii） diffraction phenomena of incident coherent light. Furthermore, for femtosecond pulses, the structure induces （iv） an optical delay equivalent to a consecutive temporal delay of 230 fs in places of the pulse. These features enable studying experimentally and numerically the effect of tuning both pulse duration τ and spectral bandwidth Δω on the features of the wideangle scattering pattern from the riblet structure. As a result, we discovered a significant breakdown of fringes in the scattering pattern with decreasing pulse duration and/or increasing spectral bandwidth. This unique type of chirp control is straightforward/y explained and verified by numerical modeling considering the spectral and temporal interaction between different segments within the scattered, linearly chirped pulse and the particular geometric features of the riblet structure. The visibility of the fringe pattern can be precisely adjusted, and the offstate is achieved using τ 〈 230 fs or Δω〉 2.85 × 10^13 rad/s.
基金This work was financially supported by the Deutsche Forschungsgemeinschaft(project INST 190/137-1)and the Ministry of Science and Culture of Lower Saxony(MWK).
文摘The implementation of photoinduced linkage isomerism in molecular-based optical materials represents a promising approach for the synthesis of high-contrast,high-resolution photosensitive materials that are necessary for high-density(holographic)data storage and/or real-three-dimensional(holographic)displays.The unsolved task of embedding a photofunctional coordination complex into a matrix like polymer polydimethylsiloxane(PDMS)with photoinduced isomerism of a SO-bond in the sulfoxide compoundRubpy2OSOPF6 is addressed.This approach allows to preserve the spectral properties within the solid dielectric environment,with an impact of PDMS on population and relaxation dynamics.All data are discussed in the framework of photofunctionality,storage,and display applications.
