Chen Y, Chen Z, Wadsworth W J, Birks T A
Department of Physics, University of Bath, Claverton Down, Bath BA2 7AY, UK.
Opt Express. 2013 Jul 29;21(15):17786-99. doi: 10.1364/OE.21.017786.
The distinct disperion properties of higher-order modes in optical fibers permit the nonlinear generation of radiation deeper into the ultraviolet than is possible with the fundamental mode. This is exploited using adiabatic, broadband mode convertors to couple light efficiently from an input fundamental mode and also to return the generated light to an output fundamental mode over a broad spectral range. For example, we generate visible and UV supercontinuum light in the LP(02) mode of a photonic crystal fiber from sub-ns pulses with a wavelength of 532 nm.
光纤中高阶模独特的色散特性使得非线性产生的辐射能够深入到比基模所能达到的更深的紫外区域。利用绝热宽带模式转换器可以有效地将光从输入基模耦合出来，并在宽光谱范围内将产生的光返回到输出基模。例如，我们利用波长为532 nm的亚纳秒脉冲在光子晶体光纤的LP(02)模式中产生了可见光和紫外超连续谱光。
