Spatiotemporal evolution of high-aspect-ratio filamentary trace in sapphire of picosecond pulse burst-mode for laser lift-off

The influence of the picosecond(ps) pulsed burst with a nanosecond scale of temporal separation(50 ns) on filamentary traces in sapphire substrate is investigated. The spatiotemporal evolution of the filamentary plasma string induced by sub-pulses of the burst-mode is revealed according to the analysis of the instantaneous photoluminescence images. Due to the presence of residual plasma, the energy loss of sub-pulse during the balancing of self-focusing effect is reduced, and thus refreshes the plasma via refocusing. The refreshed plasma peak generated by the subsequent subpulse appears at relatively low density positions in the formed filamentary plasma string, which results in more uniform densities and less spatial overlap among the plasma peaks. The continuity and uniformity of the filamentary trace in sapphire are enhanced by the burst-mode. Besides, the burst filamentary propagation can also remain effective when the sub-pulse energy is below the self-focusing threshold. Based on this uniform and precise energy propagation mode, the feasibility of its use for the laser lift-off(LLO) process is verified.

探究基于物联网的智能家居系统

传统的智能家居大部分是通过有线的方式组成智能家居系统，这种方式不仅需要专业人员的参与、专门公司维护，而且施工周期长，系统灵活性差。而物联网智能家居则是将无线物联网技术和智能家居有机地融合在一起，从而构建一个安装简单、使用方便、维护容易、扩展随心所欲的智能家居系统。但智能家居系统在发展中也存在很多问题，需要我们亟待解决。

柔性电子制造领域的超快激光技术:机制、特征功用及挑战(特邀)

随着智能化时代的到来,柔性电子由于其极强的共形能力和优异的器件性能,在进一步推动现代化产业发展中取得越来越重要的地位。超快激光技术以其优异的高精制造能力在柔性电子高分辨无损制备上展示出独特的优势和应用前景。本文从超快激光与物质相互作用基本机制入手,着重介绍了当前超快激光在柔性电子领域的四种典型特征功用及其研究现状,并据此总结该领域超快激光应用所面临的挑战和未来发展趋势。

面向临床手术的激光钻切骨孔微观组织及抗失稳行为

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飞秒贝塞尔光束直写铌酸锂高深径比光子晶体结构

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