A cylindrical Öffner stretcher based on ternary reflector (COSTER) is proposed and analyzed. Compared with the traditional Öffner stretcher, the COSTER has no off-axis aberration in the multipass configuration, and the output laser of COSTER has lower spectral phase noise and higher temporal contrast in the far field. The COSTER is quite suitable to be used in multi-petawatt laser facilities, and it might be the preferred stretcher configuration for ultrafast and ultra-intense lasers.

Visible light communication (VLC) is an emerging technology employing light-emitting diodes (LEDs) to provide illumination and wireless data transmission simultaneously. Harnessing cost-efficient printable organic LEDs (OLEDs) as environmentally friendly transmitters in VLC systems is extremely attractive for future applications in spectroscopy, the internet of things, sensing, and optical ranging in general. Here, we summarize the latest research progress on emerging semiconductor materials for LED sources in VLC, and highlight that OLEDs based on nontoxic and cost-efficient organic semiconductors have great opportunities for optical communication. We further examine efforts to achieve high-performance white OLEDs for general lighting, and, in particular, focus on the research status and opportunities for OLED-based VLC. Different solution-processable fabrication and printing strategies to develop high-performance OLEDs are also discussed. Finally, an outlook on future challenges and potential prospects of the next-generation organic VLC is provided.

研究了向列相液晶激光器件侧面激光辐射谱，并深入分析了激光辐射机制。分别制备了传统液晶盒和引入SU-8光栅结构的两种器件，并注入向列相液晶TEB30A和激光染料PM597的混合物。利用Nd：YAG固体脉冲激光器倍频出的532 nm激光作为泵浦源正面入射器件，侧面探测激光辐射谱。在传统液晶盒器件侧面，测得 575~600 nm范围的随机激光辐射谱。而具有周期100 μm和8 μm 的SU-8光栅结构器件侧面，获得了多波长激光辐射谱。随着泵浦能量增大，最高强度激光辐射峰波长位置出现在583~585 nm和588~592 nm附近，FWHM约0.3 nm。基于光波导理论结合器件结构分析得出，在传统液晶盒中引入SU-8光栅结构增强了液晶器件的光波导效应，是获得多波长激光辐射谱的主要原因。

Ultraintense short-period infrared laser pulses play an important role in frontier scientific research, but their power is quite low when generated using current technology. This paper demonstrates a scheme for generating an ultraintense few-cycle infrared pulse by directly compressing a long infrared pulse. In this scheme, an infrared picosecond-to-nanosecond laser pulse counterpropagates with a rapidly extending plasma grating that is created by ionizing an undulated gas by a short laser pulse, and the infrared laser pulse is reflected by the rapidly extending plasma grating. Because of the high expansion velocity of the latter, the infrared laser pulse is compressed in the reflection process. One- and two-dimensional particle-in-cell simulations show that by this method, a pulse with a duration of tens of picoseconds in the mid- to far-infrared range can be compressed to a few cycles with an efficiency exceeding 60%, thereby making ultraintense few-cycle infrared pulses possible.