1,720,970 research outputs found
Three-level fiber DFB laser at 980 nm
No full textA three-level fiber DFB-laser operating at 977nm is demonstrated for the first time using a 910nm pump diode. The fiber DFB laser shows 17.5mW output power under a launching power of 113mW
977-nm all-fiber DFB laser
No full textThree-level operation of a fiber distributed feedback (DFB) laser operating around 980nm is demonstrated for the first time. The ytterbium-doped DFB laser shows a maximum slope efficiency of 61% and output power of 38.2mW under a launched single-mode pump power of 150mW at 910nm. The efficiency of lasers with different coupling strengths and at different pump wavelengths is also investigated
Relaxation oscillation noise suppression in fibre DFB lasers using a semiconductor optical amplifier
No full textWe report the experimental results of a simple, all optical technique to reduce the relative intensity noise peak of a fibre distributed feedback laser. A noise reduction of 30dB is achieved
Intensity noise suppression in fibre DFB laser using gain saturated SOA
No full textExperimental results of a simple, all-optical technique to reduce low-frequency intensity noise in an Er-Yb codoped fibre distributed feedback (DFB) laser are reported. This method utilises the gain dynamics of a saturated semiconductor optical amplifier (SOA) to produce a reduction of 30dB in the relaxation oscillation noise component of the fibre laser
Keyed axis single-polarisation all-fibre DFB laser
No full textA single-polarised D-shaped fibre DFB laser with keyed axis output is demonstrated. The laser shows an output power of 3.8 dBm and strong axis alignment when spliced to a polarisation maintaining fibre
Erbium-ytterbium L-band fibre-DFB laser pumped at 1534nm
No full textAn L-band (1618nm) fibre-DFB laser pumped at 1534nm is demonstrated for the first time. It has a threshold of <10mW and up to 2mW of optical power in a single-polarisation with a line-width of ~8kHz
Single-polarization all-fibre DFB laser with keyed axis output
No full textA single-polarized fiber DFB laser with keyed axis output is demonstrated from a D-shaped fiber configuration. The laser shows an output power of 3.8dBm and strong axis alignment when spliced to a polarization maintaining fiber
Compact high-power tunable three-level operation of double cladding Nd-doped fiber laser
Full text linkWe present a compact high-power continuous-wave tunable neodymium-doped double cladding fiber laser operating on three-level 4F3/2 - 4I9/2 transition with a maximum output power up to 810 mW. At 926.7 nm, it has a maximum slope efficiency of 49.3% against absorbed 808-nm pump. By compressing the fiber Bragg grating, 15-nm tuning range is achieved
All-fibre Bragg grating filters and lasers for future optical networks
No full textBragg gratings in optical fibre waveguides have now been around for 25 years and they were soon after being realised, identified as one of the most significant fibre-optic inventions with potentials in a wide variety of areas among telecommunications equivalent to that of the erbium doped fibre amplifier. Following their creation a plurality of in-fibre functions were thought possible with low or no insertion-loss. Although fabrication and control of vital grating parameters was limited in the early stages of their life, initially a number of filtering functions were identified for obvious demonstrations. It soon became apparent though that not just standard filtering manipulation was possible. Identifying the true potential of the devices has let to considerable effort being concentrated on their full exploitation implying building an infrastructure supported by theoretical design and manufacturing techniques around them. These techniques combined have let to a scenario where currently it is the imagination more than the actual design and manufacturing capabilities that imposes a limitation to what is being demonstrated and now they find applications in most of the modern telecommunications network. Cladding-pumped fibre technology has revolutionised fibre lasers over the last decade, increasing output power from less than 1 W with traditional core-pumping to well over 100 W. Even 1 kW of power has been reached in multi-mode designs, when several devices have been arranged in series or in parallel. For output powers below 100W, a few diode bars or multi-emitter laser diode assemblies are adequate pump sources. However, for powers beyond the 100 W level, diode stacks seem to be a better choice. The increasing availability of suitable diode stacks and the possibility of efficient fibre launch make them very attractive for pumping of high-power fibre-lasers. At the same time, while fibres proved very reliable at powers up to ~100 W, it is clear that further power-scaling to the kW level with diode stack pumping requires significant fibre optimisation in terms of fibre composition, pump coupling, and/or overall device layout. This is especially true when a single-mode output is required. We will in this presentation discuss and highlight some of the most recent advances in Bragg grating devices and applications in advanced components together with the most recent advances in the area of high power fibre lasers. In particular we will show examples of the latest in Bragg gratings for dispersion-control, short pulse-manipulation, advanced filtering applications together with some of our 1kW and speculate into what the future holds for Bragg gratings and high-power lasers and amplifiers
A 16-channel OCDMA system (4 OCDMA x 4 WDM) based on 16-chip, 20 Gchip/s superstructure fibre Bragg gratings and DFB fibre laser transmitters
No full textWe demonstrate an all-fibre OCDMA system comprising 16 channels (4 OCDM x 4 WDM, 100 GHz grid) incorporating DFB fibre lasers as transmitters and 16-chip, 20 Gchip/s quaternary phase superstructured fibre Bragg gratings. Error free performance at 311 Mbit/s was obtained for all 16 channels for transmission distances of up to 50km of standard fibre without the need for dispersion compensation or nonlinear optical thresholding
- …
