Modal content in hypocycloid Kagome hollow core photonic crystal fibers

作者：Bradley Thomas D^*; Wheeler Natalie V; Jasion Gregory T; Gray David; Hayes John; Gouveia Marcelo Alonso; Sandoghchi Seyed R; Chen Yong; Poletti Francesco; Richardson David; Petrovich Marco

来源：Optics Express, 2016, 24(14): 15798-15812.

DOI：10.1364/OE.24.015798

The modal content of 7 and 19 cell Kagome anti resonant hollow core fibers (K-ARF) with hypocycloid core surrounds is experimentally investigated through the spectral and spatial (S-2) imaging technique. It is observed that the 7 and 19 cell K-ARF reported here, support 4 and 7 LP mode groups respectively, however the observation that K-ARF support few mode groups is likely to be ubiquitous to 7 and 19 cell K-ARFs. The transmission loss of the higher order modes (HOMs) was measured via S-2 and a cutback method. In the 7 cell KARF it is found that the LP11 and LP21 modes have approximately 3.6 and 5.7 times the loss of the fundamental mode (FM), respectively. In the 19 cell it is found that the LP11 mode has approximately 2.57 times the loss of the FM, while the LP02 mode has approximately 2.62 times the loss of the FM. Additionally, bend loss in these fibers is studied for the first time using S-2 to reveal the effect of bend on modal content. Our measurements demonstrate that K-ARFs support a few mode groups and indicate that the differential loss of the HOMs is not substantially higher than that of the FM, and that bending the fiber does not induce significant inter modal coupling. A study of three different input beam coupling configurations demonstrates increased HOM excitation at output and a non-Gaussian profile of the output beam if poor mode field matching is achieved. Published by The Optical Society under the terms of the Creative Commons Attribution 4.0 License.

• 出版日期2016-7-11