Understanding wavelength scaling in 19-cell core hollow-core photonic bandgap fibers

First experimental wavelength scaling in 19-cell core HC-PBGF indicates that the minimum loss waveband occurs at longer wavelengths than previously predicted. Record low loss (2.5dB/km) fibers operating around 2µm and gas-purging experiments are also reported

30.7 Tb/s (96x320 Gb/s) DP-32QAM transmission over 19-cell photonic band gap fiber

We report for the first time coherently-detected, polarization-multiplexed transmission over a photonic band gap fiber. By transmitting 96 x 320-Gb/s DP-32QAM modulated channels, a net data rate of 24 Tb/s was obtained

Hollow core fibres for high capacity data transmission

We review our progress in developing, characterizing and handling hollow-core photonic bandgap fibers with improved transmission properties, targeted at high-capacity, low-latency data transmission in the current telecoms window and at the potentially lower-loss 2µm wavelengths

First Demonstration of a Broadband 37-cell Hollow Core Photonic Bandgap Fiber and Its Application to High Capacity Mode Division Multiplexing

We report fabrication of the first low-loss, broadband 37-cell photonic bandgap fiber. Exploiting absence of surface modes and low cross-talk in the fiber we demonstrate mode division multiplexing over three modes with record transmission capacity

Transmitting data inside a hole: recent advances in hollow core photonic bandgap technology

We review our recent progress in the fabrication, characterization, modeling and splicing of wide transmission bandwidth hollow core photonic bandgap fibers and discuss their modal properties and potential for data transmission

First demonstration of a broadband 37-cell hollow core photonic bandgap fiber and its application to high capacity mode division multiplexing

We report fabrication of the first low-loss, broadband 37-cell photonic bandgap fiber. Exploiting absence of surface modes and low cross-talk in the fiber we demonstrate mode division multiplexing over three modes with record transmission capacity

Unified Coupled-Mode Theory for Geometric and Material Perturbations in Optical Waveguides

Coupled-mode theory is a powerful tool to understand and control the effects of deployment and fabrication imperfections on optical waveguides. Although it provides many advantages compared to the finite element method, it still lacks the ability to treat geometric and material perturbations when they act simultaneously on the waveguide. This work fills this gap, providing a novel framework for a unified treatment of geometric and material perturbations in the coupled-mode analysis. The proposed approach consists of, first, applying the theory of transformation optics to convert geometric deformation into material perturbations and, second, studying the obtained waveguide by using a custom-developed coupled-mode theory able to deal with perturbations of both the permittivity and the permeability tensor. The framework is applied to three examples: a solid-core fiber affected by intrinsic perturbations, a bent solid-core fiber, and an elliptical hollow-core fiber. Results are validated against simulations based on the finite element method and compared with the standard coupled-mode theory most suitable for each specific example; they show that the proposed unified coupled-mode theory performs consistently better than standard theories, confirming it as a general and accurate tool for the design and analysis of optical waveguides

Optical side scattering radiometry for high resolution, wide dynamic range longitudinal assessment of optical fibers

Current optical reflectometric techniques used to characterize optical fibers have to trade-off longitudinal range with spatial resolution and therefore struggle to provide simultaneously wide dynamic range (>20dB) and high resolution (<10cm). In this work, we develop and present a technique we refer to as Optical Side Scattering Radiometry (OSSR) capable of resolving discrete and distributed scattering properties of fibers along their length with up to 60dB dynamic range and 5cm spatial resolution. Our setup is first validated on a standard single mode telecoms fiber. Then we apply it to a record-length 11km hollow core photonic band-gap fiber (HC-PBGF) the characterization requirements of which lie far beyond the capability of standard optical reflectometric instruments. We next demonstrate use of the technique to investigate and explain the unusually high loss observed in another HC-PBGF and finally demonstrate its flexibility by measuring a HC-PBGF operating at a wavelength of 2µm. In all of these examples, good agreement between the OSSR measurements and other well-established (but more limited) characterization methods, i.e. cutback loss and OTDR, was obtained

A novel approach to coupled-mode analysis of geometric deformations in reciprocal waveguides

We present an approach to treat geometric perturbations in coupled-mode analysis for reciprocal waveguides. Geometric perturbations are converted into material ones and a coupled-mode theory for material perturbations is used to assess the propagation. The method is tested on an elliptically deformed antiresonant fiber