Fast and broadband fiber dispersion measurement with dense wavelength sampling

We report on a method to obtain dispersion measurements from spectral-domain low-coherence interferograms which enables high accuracy (~ps/(nm·km)), broadband measurements and the determination of very dense (up to 20 points/nm over 500 nm) data sets for both dispersion and dispersion slope. The method exploits a novel phase extraction algorithm which allows the phase associated with each sampling point of the interferogram to be calculated and provides for very accurate results as well as a fast measurement capability, enabling close to real time measurements. The important issue of mitigating the measurement errors due to any residual dispersion of optical elements and to environmental fluctuations was also addressed. We performed systematic measurements on standard fibers which illustrate the accuracy and precision of the technique, and we demonstrated its general applicability to challenging problems by measuring a carefully selected set of microstructured fibers: a lead silicate W-type fiber with a flat, near-zero dispersion profile; a hollow core photonic bandgap fiber with strongly wavelength dependent dispersion and dispersion slope; a small core, highly birefringent index guiding microstructured fiber, for which polarization resolved measurements over an exceptionally wide (~1000 nm) wavelength interval were obtained

Er-doped Oxidized Porous Silicon Waveguides

The present work reports Er-doped channel oxidized porous silicon waveguides (OPSWG) formed from n+-type Si by the two-step anodisation process. Er has been introduced into porous silicon before oxidation by a cathodic treatment in 0.1 M Er (NO3)3 aqueous solution. A correlation between Er concentration and refractive index profiles has shown dominant core doping with Er relative to cladding regions. Reported Er concentration of 0.8 at.% in the OPSWG is large enough to attain the amplification effect

A multi-core fiber to single-mode fiber side-polished coupler

Evanescent coupling between a side-polished multi-core fiber and a single-mode fiber is demonstrated for the first time. The low-loss tap coupler is capable of isolating the output from a single core of a 7-core fiber

All-Optical Programmable Disaggregated Data Centre Network realized by FPGA-based Switch and Interface Card

This paper reports an FPGA-based switch and interface card (SIC) and its application scenario in an all-optical, programmable disaggregated data center network (DCN). Our novel SIC is designed and implemented to replace traditional optical network interface cards, plugged into the server directly, supporting optical packet switching (OPS)/optical circuit switching (OCS) or time division multiplexing (TDM)/wavelength division multiplexing (WDM) traffic on demand. Placing the SIC in each server/blade, we eliminate electronics from the top of rack (ToR) switch by pushing all the functionality on each blade while enabling direct intrarack blade-to-blade communication to deliver ultralow chip-to-chip latency. We demonstrate the disaggregated DCN architecture scenarios along with all-optical dimension-programmable N × M spectrum selective Switches (SSS) and an architecture-on-demand (AoD) optical backplane. OPS and OCS complement each other as do TDM and WDM, which can support variable traffic flows. A flat disaggregated DCN architecture is realized by connecting the optical ToR switches directly to either an optical top of cluster switch or the intracluster AoD optical backplane, while clusters are further interconnected to an intercluster AoD for scaling out

Demostración de un sensor de gas metano basado en un sistema de acoplo de múltiples secciones de fibra de cristal fotónico

Hollow-core photonic bandgap fibres (HC-PBFs) have been recently demonstrated as a powerful technology in the field of gas sensing. The long interaction path lengths available with these fibers are advantageous for the detection of weakly absorbing gases such as methane. However, long path lengths also yield to very high insertion times of the gas into the fiber. In this paper, a novel solution based on a multicoupling gap system to detect methane with HC-PBFs is proposed. For that purpose, a conventional configuration using one long piece of HC-PBF is compared to this novel method, which uses shorter pieces of HC-PBF with the same overall length as the previous configuration. The results and conclusions from experimental studies are presented and discussed. The multicoupling gap system is demonstrated to considerably reduced the filling time while maintaining the sensitivity, proving the feasibility of the configuration proposed

First demonstration of 2μm data transmission in a low-loss hollow core photonic Bandgap fiber

The first demonstration of a hollow core photonic bandgap fiber suitable for high-rate data transmission at 2µm is presented. Using a custom built Thulium doped fiber amplifier, error-free 8Gbit/s transmission in an optically amplified data channel at 2008nm is reported for the first time

Fibre optical sensor for C₂H₂ gas using sealed arc fusion spliced gas filled PBGF reference cell

It is of great importance to develop gas sensing techniques which are selective, quantitative, fast-acting and not susceptible to poisoning. Spectroscopic optical gas sensors, especially those capable of remote sensing over optical fibres, are highly attractive for fast real-time detection and measurement of many gases [1]. One highly selective optical gas sensing method is correlation spectroscopy (CS) [2], in which a reference sample of target gas is held fixed within the interrogation system to act as a spectral reference, and is then compared with the spectrum of the test gas to obtain the measurement. We have suggested that a Photonic Bandgap Fibre (PBGF), filled with the target gas, provides a very effective and compact reference, with a clear advantage over traditional linear cells, which are bulky, intricate, fragile, difficult to align and expensive [3]