Kagome光纤超快非线性光学研究进展

Ultrafast nonlinear optics in Kagome fibers

Kagome光纤(简称KGF)是一种不依赖带隙导光的新型空芯微结构光纤,其结构设计灵活、损伤阈值高、损耗低(高透区损耗可低至~40 dB/km)、支持宽带传输(>500 nm),并可通过纤芯改变所充气体及调节气压实现光纤色散、非线性效应的有效调制,在强场物理、超快激光技术等领域研究中优势突出。基于KGF在超快光学中的重要意义,该文对近年来国际上关于KGF在非线性光学变频及超短脉冲压缩等领域的研究成果进行介绍,并对关键性应用技术进行简要分析,最后对其发展前景进行展望。

Kagome fiber （KGF） is a new type of microstructure optical fiber, in which light guidance is not completely dependent on the photonic bandgap. This fiber displays some outstanding features such as flexible structure design, high damage threshold, low loss （as low as -40 dB/km at high transmission wavelengths）, and wide transmitting bandwidth （〉500 nm）. In particular, by adjusting the gas pressure in the fiber＇s hollow core, its nonlinearity and dispersion properties can be modulated easily for various important applications, including strong field physics, ultrafast nonlinear optics, and ultrashort pulse compression technology. In this paper we review the major experimental and theoretical progress achieved in recent years in KGF applications based on nonlinear optical frequency conversion and ultrashort pulse compression, then analyse the key technology behind their advanced applications. Finally, we assess the prospects for further applications of this novel fiber.