Polarization maintaining mode selective coupler

Simple all-fiber coupler is presented as solution to the missing MDM component in the future all fiber networks. It is capable of exciting specific higher order mode at the required spatial direction with high efficiency

Low loss kagome fiber in the 1µm wavelength region

We present a Kagome hollow core fiber with record low loss (12.3dB/km at 1010nm), a wide 3dB bandwidth (150nm), low bend sensitivity and large mode field diameter (~30µm), tailored for high power delivery applications

Modal content in hypocycloid Kagomé hollow core photonic crystal fibers

The modal content of 7 and 19 cell Kagomé anti resonant hollow core fibers (K-ARF) with hypocycloid core surrounds is experimentally investigated through the spectral and spatial (S2) 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 S2 and a cutback method. In the 7 cell K-ARF 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 S2 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

S2 measurement of higher order mode content in low loss hypocycloid Kagomé hollow core photonic crystal fiber

We present the first detailed investigation of modal properties in hypocycloid Kagomé fibers; even with an optimized input launch, higher order modes propagate over long fiber lengths, indicative that these modes have low attenuation

Design and optimization of a microfiber coupler for biosensing

We design and optimize a simple, low-cost and compact biosensor based upon a microfiber coupler, with a predicted sensitivity and detection limit up to S~104 nm/RIU and DL~10-6 RIU respectively

Dataset for Modal Content in Hypocycloid Kagomé Hollow Core Photonic Crystal Fibers

The modal content of 7 and 19 cell Kagom&eacute; anti resonant hollow core fibers (K-ARF) with hypocycloid core surrounds is experimentally investigated through the spectral and spatial (S2) 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 S2 and a cutback method. In the 7 cell K-ARF it is found that the LP11 and LP21 modes have approximately 3.6 and 5.8 times the loss of the fundamental mode (FM), respectively. In the 19 cell it is found that the LP11 mode has approximately 2.6 times the loss of the FM, while the LP02 mode has approximately 2.6 times the loss of the FM. Additionally, bend loss in these fibers is studied for the first time using S2 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 content and a non-Gaussian profile of the output beam if poor mode field matching is achieved.</span

Mid-IR Hollow-core microstructured fiber drawn from a 3D printed PETG preform

Mid-infrared (mid-IR) optical fibers have long attracted great interest due to their wide range of applications in security, biology and chemical sensing. Traditionally, research was directed towards materials with low absorption in the mid-IR region, such as chalcogenides, which are difficult to manipulate and often contain highly toxic elements. In this paper, we demonstrate a Polyethylene Terephthalate Glycol (PETG) hollow-core fiber (HCF) with guiding properties in the mid-IR. Guiding is provided by the fiber geometry, as PETG exhibits a material attenuation 2 orders of magnitude larger than the HCF propagation loss. The structured plastic fiber preforms were fabricated using commercial 3D printing technology and then drawn using a conventional fiber drawing tower. The final PETG fiber outer diameter was 466 µm with a hollow-core diameter of 225 µm. Thermal imaging at the fiber facet performed within the wavelength range 3.5 – 5 µm clearly indicates air guidance in the fiber hollow core