High-power femtosecond mid-infrared (MIR) lasers are of vast importance to both fundamental research and applications. We report a high-power femtosecond master oscillator power amplifier laser system consisting of a single-mode Er:ZBLAN fiber mode-locked oscillator and pre-amplifier followed by a large-mode-area Er:ZBLAN fiber main amplifier. The main amplifier is actively cooled and bidirectionally pumped at 976 nm, generating a slope efficiency of 26.9%. Pulses of 8.12 W, 148 fs at 2.8 μm with a repetition rate of 69.65 MHz are achieved. To the best of our knowledge, this is the highest average power ever achieved from a femtosecond MIR laser source. Such a compact ultrafast laser system is promising for a wide range of applications, such as medical surgery and material processing.

Luminescent materials often suffer from thermal quenching (TQ), limiting the continuation of their applications under high temperatures up to 473 K. The formation of defect levels could suppress TQ, but rational synthesis and deep understanding of multiple defects-regulated luminescent materials working in such a wide temperature range still remain challenging. Here, we prepare a negative thermal quenching (NTQ) phosphor LiTaO₃ : Tb^{3 +} by introducing gradient defects VTa5-,TbLi2+, and ( V_TaTb_Li)^{3 -} as identified by advanced experimental and theoretical studies. Its photoluminescence significantly becomes intense with rising temperatures and then slowly increases at 373 to 473 K. The mechanism studies reveal that gradient defects with varied trapping depths could act as energy buffer layers to effectively capture the carriers. Under thermal disturbance, the stored carriers could successively migrate to the activators in consecutive and wide temperature zones, compensating for TQ to enhance luminescence emission. This study initiates the synthesis of multi-defect NTQ phosphors for temperature-dependent applications.

高通量制备可通过并行合成策略快速获得大量成分准连续或梯度变化的样品, 从中筛选出具有最佳成分与性能的目标材料, 将传统的“试错法”研发模式变革为系统寻优的新模式, 可以显著提高研发效率。高通量制备实验还可与材料计算和机器学习等虚拟实验相辅相成, 验证计算结果, 并为数据挖掘和应用提供更丰富的实验基础。本文综述了微纳粉体样品库高通量并行合成方法和进展, 这些典型的高通量制备方法为功能粉体材料研发工作者加速实验进程提供了新思路和高效合成路径, 已应用于催化剂、荧光粉、红外辐射材料、电催化材料等的快速发现和优选, 并将不断扩大应用领域和规模, 凸显其先进性和应用价值。