Characterization of optical isolator free#

The C-lens was first carefully inserted into the ferrule sleeve and fixed with UV curable adhesive. In order to minimize Fresnel reflection, the few-mode fiber was angle-cleaved at an 8° angle (or polished for a higher-quality surface) and a C-lens was prepared with both anti-reflection coatings and an 8° facet angle. Compact fiber optic collimators usually use C-lens (or GRIN lens) elements to transform the emergent light from an input FMF into a collimated free-space beam that can then be refocused into another length of FMF using a second identical assembly operated in reverse. Richardson, “ Compact few-mode fiber collimator and associated optical components for mode division multiplexed transmission,” in Optical Fiber Communication Conference (2016) ( IEEE, 2016), p.

Due to the simple fabrication process, good beam transfer quality, and low cost, these devices represent an extremely attractive means to reduce the cost of building and operating SDM systems.įigure 1(a) shows a schematic diagram of a few-mode fiber (FMF) isolator assembly consisting of a cylindrical micro-optic lens and a few mode fiber ferrule, fitted in a ferrule sleeve. Richardson, “ Compact 32-core multicore fibre isolator for high-density spatial division multiplexed transmission,” in European Conference on Optical Communication (ECOC) ( VDE, 2016), p. In this paper, we review our recent work to incorporate SDM fibers (e.g., few mode fibers and multicore fibers) in a micro-optic collimator assembly and investigate the feasibility of demonstrating fully integrated optical isolators for SDM transmission note that provisional results were reported in Refs. Riza, “ General formula for coupling-loss characterization of single-mode fiber collimators by use of gradient-index rod lenses: Errata,” Appl.

Characterization of optical isolator free#

Current micro-optic collimators usually use graded-index (GRIN) lens or C-lens elements to transform the light from an input single mode optical fiber into a collimated free space beam and to refocus it into an output single mode fiber in a compact and cost effective manner. An optical fiber collimator (i.e., fiber optic collimation and focusing assembly) represents an important platform for the realization of many commonly used fiber optic components and devices including optical isolators, circulators, gain flattening filters, WDM couplers, switches, and variable optical attenuators. From this perspective, a fiber-optic approach will inevitably be the preferred route forward and the fabrication of fully fiberized components is a pre-requisite for realizing practical SDM systems.

These are not only bulky but also expensive and tend to introduce high optical losses. Richardson, “ First demonstration and detailed characterization of a multimode amplifier for space division multiplexed transmission systems,” Opt. de Waardt, “ 73.7 Tb/s (96 × 3 × 256-Gb/s) mode division multiplexed DP-16QAM transmission with inline MM-EDFA,” Opt. Lingle, “ Mode-division multiplexing over 96 km of few-mode fiber using coherent 6 × 6 MIMO processing,” J. Unlike widely used single-mode fiber systems, however, the essential components needed to build SDM systems or optical fiber sensor systems based on SDM fibers are still not commercially available and the basic prototype systems used in many experiments to date have been implemented only with the aid of bulky free-space optical components. More recently, SDM technologies are being investigated for many other applications such as (i) submarine networks to increase both single fiber capacity and energy efficiency, (ii) datacenter networks to reduce cable count and complexity whilst increasing data bandwidth, and (iii) optical fiber sensor systems to enable long distance distributed sensing or 3-dimensional shape sensing. utilizing few-mode fibers or multicore fibers (MCFs) supporting multiple spatial channels is currently under intense investigation as an efficient approach to overcome the current capacity limitations of high-speed long-haul transmission systems based on single mode optical fibers. Matsuo, “ Multicore fiber technology,” J. Winzer, “ Making spatial multiplexing a reality,” Nat. Nelson, “ Space-division multiplexing in optical fibres,” Nat.