Fibre amplifier

C. G. Atkins, J. F. Massicott, J. R. Armitage, R. Wyatt, B. J. Ainslle and S. P. Craig-Ryan, High-gain, broad spectral bandwidth erbium-doped fibre amplifier pumped near 1.5 im. Electron. Lett., 25 [14], 910-911 July 6, 1989. 

Becker, EC., J.R. Simpson and N. Olsson, 1996, Erbium Fibre Amplifiers, Fundamentals and Technology (Academic Eress, New York). 

Desurvire, E., 1994, Erbium-doped Fibre Amplifiers Principles and Applications (Wiley, New York). 

Str k, W., C. Szafianski, E. Lukowiak, Z. Mazurak and B. Jerowska, 1977, Phys. Status Solidi 41, 547. Struck, C.W., and W.H. Fonger, 1991, Radiative and non-radiative rates in luminescence centers, in Advances in Non-Radiative Processes in Solids, ed. B. Di Bartolo (Plenum Press, New librk) p. 63. Sunak, H.R.D., 1991, Bibliography on Erbium Doped Fibre Amplifiers 1987 to 1990 (EDFA Consultants). 

Mori A., Ono H., Shikano K., and Shimizu M., 980 nm band pumped Er -doped tellurite-based fibre amplifier with low-noise figure of less than 4.5 dB., Electron. Lett., 38,1419-1420 (2002). 

Mori A., Kobayashi K., Yamada M., Kanamori T., Oikawa K., Nishida Y., and Ohishi Y, Low noise broadband tellurite-based Er -doped fibre amplifiers. Electron. Lett, 34,887-888 (1998). 

Makino T., Sotobayashi H., and Chujo W, 1.5 Tbit/s (75 20 Gbit/s) DWDM transmission using Er -doped tellurite fibre amplifiers with 63 nm continuous signal band. Electron. Lett., 38,1502-1504 (2002). 

Rare Earth Ions. - The use of rare earth doped glasses in miniature optical devices will require doping to much higher levels than in existing fibre amplifiers. Clustering of the rare earth ions is deleterious to the optical performance and may occur at levels of a few tenths of 1 mol%. A multi-frequency study of a... 

Y. Miyajima, T. Komukai, T. Sugawa and T. Yamamoto, Rare earth-doped fluoride fibre amplifiers and fibre lasers. Opt. Fibre Technol., 1, 35-47 (1994). 

A modern spectrophotometer (UV/VIS, NIR, mid-IR) consists of a number of essential components source optical bench (mirror, filter, grating, Fourier transform, diode array, IRED, AOTF) sample holder detector (PDA, CCD) amplifier computer control. Important experimental parameters are the optical resolution (the minimum difference in wavelength that can be separated by the spectrometer) and the width of the light beam entering the spectrometer (the fixed entrance slit or fibre core). Modern echelle spectral analysers record simultaneously from UV to NIR. 

As an alternative to planar waveguiding structures we report here the fabrication of crystal cored fibres in which it is possible to maintain uniform guide dimensions over long lengths. These fibres with organic crystal core material having large second order non-linearity could be used for miniaturization of visible laser sources and realization of parametric amplifiers for optical communications. 

Losses still occur in the fibres developed for commercial use. Nonetheless, these have been reduced to a point where transmission over kilometres is possible. Along with transmission of information in telephone systems and similar applications, it has been suggested that optical devices may replace conventional electronics in more advanced applications such as computers. For such applications, it will be necessary to develop optical switches, amplifiers, and so on. In the last two decades, new materials have been developed that may form the basis of integrated optical circuits. These materials are photonic crystals. 

It is ironic to consider the III-V nitrides, the premier materials for short wavelength blue and UV emitters, as sources of infrared light. However, Er-doped GaN is of interest for making electrically pumped, temperature insensitive, broad band and compact optical amplifiers or sources of 1.54 pm light. Applications include long-haul communication systems (amplifiers), local area networks (50/50 splitters) and sources (lasers) for transmission in silica-based optical fibres. 

Figure 9.14. Brillouin spectrometer using fibre optics to increase the signal-to-noise ratio. (1) Light source consisting of a master laser (1a) a slave with matched frequency (1b) and control unit (1c) for sensitive stabilization of the difference frequency Sv. (2) Signal splitter. (3) Fibre coupler. (4) Polarizer. (5) Chopper. (6) Lens. (7) Cuvette placed on a goniometer. (8) Termination. (9) Slit. (10) Broad-band (10 GHz) APD. (11) Photodiode with a smaller bandwidth (1 GHz). (12) Spectrum analyser (10 GHz) for controlling the intermediate frequency Sv. (13) Spectrum analyser (1 GHz) for the measurement of the half-power bandwidth, Av, of the Brillouin peak. (14) Amplifier system. (15) Process control computer. (Reproduced with permission of Elsevier, Ref [96].)...

Balakrishna S, Lomnicki S, McAvey KM, Cole RB, Dellinger B, Cormier SA (2009) Environmentally persistent free radicals amplify ultrafine particle mediated cellular oxidative stress and cytotoxicity. Part Fibre Toxicol 6 11-18 Bockhorn H (ed) (1994) Soot formation in combustion. Series in chemical physics, vol 59. Springer, Berlin... 

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