Micro/nanofibres (MNFs) are optical fibres with diameters close to or below the vacuum wavelength of visible or near-infrared light. Due to its wavelengthor sub-wavelength scale diameter and relatively large index contrast between the core and cladding, an MNF can offer engineerable waveguiding properties including optical confinement, fractional evanescent fields and surface intensity, which i...

The resonant pumping of holmium fibre lasers provides a fibre laser platform capable of addressing a wide range of applications that benefit from operation at wavelengths beyond 2.1 μm. This architecture can provide laser devices that promise high efficiency sources in the 2.1 μm spectral region with excellent beam quality and power scalability. This paper presents our recent results of resonan...

An edge-emitting laser diode is described in which the epitaxial upper cladding layer is replaced with a metal contact selected for its optical as well as electrical properties. The structure is demonstrated with an In0.1Ga0.9N multiple-quantum-well laser diode operating at 412 nm with silver rather than the typical p-type AlGaN for the upper cladding. Silver is effective as a cladding layer be...

A typical optical fiber is usually constructed of a silicon (glass) material, however, plastic and quartz are also available but normally for data transmission. Today most of all optical fibers manufactured consist of a lightconducting glass core surrounded by a thin layer of glass cladding with a lower refractive index. This cladding serves to protect the core finish. All fibers used in infrar...

We report here the fabrication, charaterisation and refractive index sensing of two microchanneled chirped fiber Bragg gratings (MCFBGs) with different channel sizes (~550μm and ~1000μm). The chirped grating structures were UVinscribed in optical fibre and the microchannels were created in the middle of the CFBGs by femtosecond (fs) laser assisted chemical etching method. The creation of microc...

A highly porous optical-fiber cladding was developed for evanescent-wave fiber sensors, which contains sensor molecules, maintains guiding conditions in the optical fiber, and is suitable for sensing in aqueous environments. To make the cladding material (a poly(ethylene) glycol diacrylate (PEGDA) polymer) highly porous, a microsphere templating strategy was employed. The resulting pore network...

The room temperature deposition of self-assembling silica nanoparticles onto D-shaped optical fibres ("D-fibre"), drawn from milled preforms fabricated by modified chemical vapour deposition (MCVD), is studied. Vertical dip-and-withdraw produces tapered layers, with one end thicker (surface coverage >0.85) than the other, whilst horizontal dip-and-withdraw produces much more uniform layers over...

In this work, the monitoring of the etching process up to a diameter of 30 μm of two LPFG structures has been compared, one of them had initially 125 μm, whereas the second one had 80 μm. By tracking the wavelength shift of the resonance bands during the etching process it is possible to check the quality of etching process (the 80 μm fibre performs better than de 125 μm fibre), and to stop for...