Sub-10-fs supercontinuum radiation generated by filamentation of few-cycle 800 nm pulses in argon.
Sub-10-fs supercontinuum radiation generated by filamentation of few-cycle 800 nm pulses in argon.
复制标题
氩气中少周期 800 nm 脉冲的丝化产生的亚 10 飞秒超连续谱辐射。
DOI：
10.1364/ol.32.002432
复制
发表时间：
2007
期刊：
影响因子：
3.6
通讯作者：
W. Schmid
中科院分区：
文献类型：
--
作者：
S. Trushin;K. Kosma;W. Fuß;W. Schmid
将中等能量(0.35 mJ)的800 nm的12fs脉冲聚焦到大气压的Ar中，产生了丝化(自聚焦)和基座非常宽的超连续谱，延伸到250 nm。根据目前的理解，短波长是由脉冲后缘自陡峭的自相位调制产生的。因此，在这个光谱范围内的脉冲可能本质上是短的。事实上，我们通过提取灯丝末端附近的光来证明这一点，通过针孔处的压力梯度终止自聚焦，超过针孔后，Ar被泵离。在不需要压缩的情况下，我们在290 nm范围内获得了9.7ps的脉冲。
Focusing 12 fs pulses of 800 nm with moderate energy (0.35 mJ) into atmospheric-pressure argon (Ar) gives rise to filamentation (self-focusing) and a supercontinuum with a very broad pedestal, extending to 250 nm. According to the present understanding, the short wavelengths are produced by self-phase modulation in the self-steepened trailing edge of the pulse. Pulses in this spectral range might thus be intrinsically short. Indeed we demonstrate this by extracting the light near the end of the filament, terminating self-focusing by a pressure gradient at a pinhole, beyond which the Ar is pumped away. We obtain pulses of 9.7 fs in the region of 290 nm without the necessity of compression.