Generation of few-cycle radially-polarized infrared pulses in a gas-filled hollow-core fiber**Project supported by the National Natural Science Foundation of China (Grant No. 61521093), the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB16), the International S & T Cooperation Program of China (Grant No. 2016YFE0119300), and the Program of Shanghai Academic/Technology Research Leader, China (Grant No.

Abstract

We perform a numerical study for temporally compressing radially-polarized (RP) infrared pulses in a gas-filled hollow-core fiber (HCF). The dynamic transmission and nonlinear compression of RP pulses centered at wavelengths of 0.8 μm, 1.8 μm, 3.1 μm, and 5.0 μm in HCFs are simulated. By comparing the propagation of pulses with the same optical cycles and intensity, we find that under proper conditions these pulses can be compressed down to 2–3 cycles. In the transverse direction, the spatiotemporal beam profile ameliorates from 0.8-μm to 1.8-μm and 3.1-μm pulses before the appearance of high-order dispersion. These results show an alternative method of scaling generation for delivering RP infrared pulses in gas-filled HCFs, which can obtain energetic few-cycle pulses, and will be beneficial for relevant researches in the infrared scope.