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Large reversible lattice strain that manipulates coupled degrees of freedom can be induced by optics in SrRuO 3 , suggesting it has great potential in optomechanical and optoelectronic devices. Photoexcitation and energy transfer via electron−phonon scattering have been studied, but recent studies inferred that more processes that remain to be identified contribute to the light-induced deformation. Here, by combining ultrafast X-ray diffraction and ultrafast optical reflectivity experiments, we image the excitation and relaxation characteristics of SrRuO 3 films. Upon photoexcitation, photocarriers redistribute both in space and energy and then relax with fast direct recombination, phonon-assisted relaxation and phonon−phonon scattering dominating on a longer time scale. The phonon-assisted relaxation process, together with the thermal effect resulting from the electron−phonon scattering on sub-picosecond time scales, contributes to the photoinduced strain in SrRuO 3 . Phonon and electron effects on relaxations of SrRuO 3 are studied, including the bottleneck effects of phonons on the coupled carrier and phonon relaxation and the scaled relationship of the fast carrier relaxation with the electron correlation. Our results suggest optomechanical and optoelectronic manipulations of SrRuO 3 by electronic pumping, providing avenues for designs of applications with high performance.

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Due to the deployment of renewable energy supplies in a smart grid (SG), various distributed power devices need to form groups dynamically to meet their requirements on power supply and demand. A communication agent or controller is coupled with each power device to exchange control state or management information with others. The underneath communication networks that enable the connections among the devices become to consist of many ad hoc groups with dynamic size and topology. Consequently, with dynamic requirement on power supply and demand, the grouping becomes a particularly challenging problem to synchronize the power devices, because the communication delays with dynamic group settings may vary frequently and significantly. In this paper, first, we propose queueing models to estimate the communication delays of the nodes in the SG. The cost of the added security to the communications is also analyzed in various scenarios. Second, we propose a smart timing adjustment algorithm with a new timing adaptive grouping (TAG) protocol, so that each agent can dynamically adjust its operational timing configuration and determine its grouping condition. Third, we develop a hardware-in-the-loop (HIL) testbed, which can be used to validate many SG applications. Finally, our experimental and simulation results on the HIL testbed have demonstrated that the proposed TAG protocol can be used to ensure the successful grouping dynamically.