Azizah Binti Hamzah

Wideband EDFA Based on Erbium Doped Crystalline Zirconia Yttria Alumino Silicate Fiber

A wideband erbium-doped fiber amplifier (EDFA) is demonstrated using an Erbium-doped zirconia fiber as the gain medium. With a combination of both Zr and Al, we could achieve a high erbium doping concentration of 4320 ppm in the glass host without any phase separations of rare-earths. The Erbium doped fiber (EDF) is obtained from a fiber preform, which is fabricated in a ternary glass host, zirconia-yttria-aluminum codoped silica fiber using a MCVD process. Doping of Er2O3 into Zirconia yttria-aluminosilicate based glass is done through solution doping process. The maximum gain of 21.8 dB is obtained at 1560 nm with 2 m long of EDF and co-pumped with 1480 nm laser diode. At high input signal of -4 dBm, a flat-gain at average value of 8.6 dB is obtained with a gain variation of less than 4.4 dB within the wavelength region of 1535-1605 nm and using 3 m of EDF and 100 mW pump power. The corresponding noise figure is maintained below 9.6 dB at this wavelength region.

Performance comparison of Zr-based and Bi-based erbium-doped fiber amplifiers.

In this Letter, we present a comprehensive comparison of the performance of a zirconia-based erbium-doped fiber amplifier (Zr-EDFA) and a bismuth-based erbium-doped fiber amplifier (Bi-EDFA). The experimental results reveal that a Zr-EDFA can achieve comparable performance to the conventional Bi-EDFA for C-band and L-band operations. With a combination of both Zr and Al, we could achieve a high erbium-doping concentration of about 2800 ppm (parts per million) in the glass host without any phase separations of rare earths. The Zr-based erbium-doped fiber (Zr-EDF) was fabricated using in a ternary glass host, zirconia-yttria-aluminum codoped silica fiber through a solution-doping technique along with modified chemical vapor deposition. At a high input signal of 0 dBm, a flat gain at average value of 13 dB is obtained with a gain variation of less than 2 dB within the wavelength region of 1530-1575 nm and using 2 m of Zr-EDF and 120 mW pump power. The noise figures are less than 9.2 at this wavelength region. It was found that a Zr-EDFA can achieve even better flat-gain value and bandwidth as well as lower noise figure than the conventional Bi-EDFA.

Hybrid flat gain C-band optical amplifier with Zr-based erbium-doped fiber and semiconductor optical amplifier

An efficient gain-flattened C-band optical amplifier is demonstrated using a hybrid configuration with a Zirconia-based Erbium-doped fibre (Zr-EDF) and a semiconductor optical amplifier (SOA). The amplifier utilizes a two-stage structure with a midway isolator to improve flat gain characteristic and reduce noise figure. At input signal power of −30 dBm, a flat gain of 28 dB is obtained from wavelength region of 1530 to 1560 nm with gain variation of less than 4 dB. The noise figure is maintained below 11 dB at the flat-gain region. This amplifier has the potential to be used in the high channel count dense wavelength division multiplexing system due to its simplicity and compact design.

Upconversion luminescence in Tm3+/Yb3+ co-doped double-clad silica fibers under 980 nm cladding pumping

An investigation is reported of the visible and near-infrared upconversions in Tm3+/Yb3+ co-doped double-clad silica fibers (TYDFs) under excitation at 980 nm. The TYDFs used were fabricated using the modified chemical vapor deposition (MCVD) and solution doping techniques. Three distinct upconversion luminescences were observed at wavelengths of 482, 649 and 816 nm and their intensities found to increase with Yb3+ concentration. The intensity of blue and red fluorescence bands at 482 and 649 nm were found to be the highest with LTY-8 fiber, which had Tm3+ and Yb3+ concentrations of 5.6 × 1019 and 15.5 × 1019 ions/cc, respectively. The upconversion luminescence intensity was also observed to decrease with an increase in temperature. The main emission switched from 482 nm to 816 nm as the temperature increased above 200°C.

Online Social Networking: A New Form of Social Interaction

Abstrac t—This paper will present the findings of the pilot studies on the use of online social network in Malaysia. A total of 40 questionnaires were distributed to active users of this social media to get an early indication on this activity. In addition, discussion about the global activities of online social networking is also undertaken as a comparison. The analysis shows that online social networking has been used as a new mode of communication especially for Internet active users to meet and interact with their friends. Early findings indicate that they spent quite many hours in this environment and log in into their accounts a few times a day. This shows that social interaction in cyberspace by using new media applications such as social networking has been adapted by more and more people and has changed human communication.

Enhanced Erbium–Zirconia–Yttria–Aluminum Co-Doped Fiber Amplifier

An efficient optical amplifier is demonstrated using an improved erbium-zirconia-yttria-aluminum co-doped fiber (Zr-EDF) as the gain medium. With a combination of both Zr and Al, we could achieve a high erbium doping concentration with an absorption loss of around 80.0 dB/m at 980 nm. The Zr-EDF is obtained from a fiber preform, which is fabricated in a ternary glass host, i.e., a zirconia-yttria-aluminum co-doped silica fiber, using a modified chemical vapor deposition, in conjunction with a solution doping process. At the optimum length of 1 m, the Zr-EDF amplifier produces a flat gain of 38 dB within a wavelength region between 1530 and 1565 nm with a gain variation of less than 3 dB when the input signal power and 980 nm pump power are fixed at

Compact fiber laser at L-band region using Erbium-doped Zirconia fiber

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Keeping ahead of the game: Innovations and challenges in e-government in Malaysia

30 dBm and 130 mW, respectively. The highest gain of 40.3 dB is obtained at 1560 nm wavelength. Compared with the previous Zr-EDF amplifier, the proposed Zr-EDFA shows improved gain, particularly at longer wavelengths. The gain is enhanced by about 15.8 dB at a wavelength of 1560 nm for an input signal of

Temperature sensor based on fluorescence measurement of Cerium Ytterbium doped fiber

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WRF model input for improved radar rainfall estimates using Kalman Filter

30 dBm.