N. A. M. Ahmad Hambali

Double Brillouin frequency shifted L-band multi-wavelength Brillouin Raman fiber laser utilizing dual laser cavity

We experimentally demonstrated a multi-wavelength Brillouin Raman fiber laser with 20 GHz spacing utilizing a dual laser cavity that operated in the L-band wavelength region. In this laser configuration, 11 km long dispersion compensating fiber provided Brillouin gain medium. At Brillouin pump (BP) wavelength of 1580 nm, BP power of 7 dBm and Raman pump power of 1259 mW, 102 Brillouin stokes signals were produced over 14.3 nm of bandwidth. By adjusting appropriate BP wavelength within 1580–1600 nm a tuning range over 20 nm was obtained. In additional, average OSNR of 21.7, 17.8, 16.9, 15.5 and 16.9 dB are recorded for wavelength at 1580, 1585, 1590, 1595 and 1600 nm respectively.

L-band multi-wavelength Brillouin-Raman fiber laser utilizing the reverse-S-shaped section

In this paper, we experimentally demonstrated multi-wavelength Brillouin–Raman fiber laser that operates in the L-band wavelength region. The laser structure utilizes the reverse-S-shaped technique. 35 output Brillouin Stokes signals were generated at the injection of 6.3 mW of Brillouin pump power at wavelength of 1580 nm into the laser cavity together with a Raman pump power of 891.25 mW. The generated output Brillouin Stokes signals are rigidly separated by 0.08 nm (10 GHz). The structure also provides a high tuning range of 25 nm, from 1570 nm to 1595 nm at the injection of 6.3 mW of Brillouin pump signal power with a Raman pump signal power of 795.3 mW. The generated Brillouin Stokes signals also have an average peak power of 1.11 mW. Highest optical signal-to-noise ratio of 21 dB was obtained at Brillouin pump wavelength of 1595 nm.

Correlation of Brillouin Stokes Signals and Optical-Signal-to-Noise-Ratio in Multi-Wavelength Brillouin Fiber Laser with Additional Fiber Bragg Grating

We experimentally demonstrate unidirectional propagation of multi-wavelength Brillouin fiber laser system with additional fiber Bragg grating. The configuration is arranged in a ring resonator by utilizing five different Brillouin gain mediums. In this experiment, the input Brillouin pump power was varied in order to maximize the generated Brillouin Stokes signals based on the respective fiber lengths. The influence of these controllable parameters leads to the correlation between of Brillouin Stokes signals and optical-signal-to-noise-ratio. In this case, at 10 km of single mode fiber the maximum of 38 Brillouin Stokes signals were generated together with 15.07 dB of average optical-signal-to-noise-ratio when the 17 dBm Brillouin pump power was launched into the ring resonator.

Lasing threshold characteristics of multi-wavelength Brillouin–erbium laser in the L-band region assisted by delay interferometer

This paper reports the simulation of L-band multi-wavelength Brillouin–erbium fiber laser that utilizes delay interferometer as a comb filter. The simulation is performed using OptiSystem. The structure exhibits threshold power in terms of Erbium doped fiber amplifier (EDFA) gain of 10mW at a very low Brillouin pump power of 0.00316mW for the generation of first Stokes. Thirty one output channels were produced with minimum EDFA gain of 1W at Brillouin pump power of 0.00316mW. In line with theory, it has been observed that higher Brillouin pump power requires low threshold gain and vice versa to generate the Brillouin Stokes.

Lasing characteristics of 10 GHz signal spacing in a ring cavity multi-wavelength Brillouin fiber laser employing fiber Bragg grating

This paper experimentally demonstrated a ring cavity multi-wavelength Brillouin fiber laser employing fiber Bragg grating (FBG) that operated in the C-band region. The FBG plays a significant role to reflect signals and filter selected wavelengths. A number of generated Brillouin Stokes (BS) signals and tuning range ability were investigated. A 9km length of single mode fiber was utilized to provide a Brillouin gain medium for generating stimulated Brillouin scattering effect. In this work, at optimum output coupling ratio of 90% and Brillouin pump (BP) wavelength of 1550nm, up to a maximum of 26 BS signals were recorded by injecting 63.1mW of amplified BP powers. The BS signals were also tunable within the ranges of 1544–1556nm in accordance with the FBG properties at 3dBm bandwidth of 5nm.

Effect of large effective area fiber length on the performance of forward-backward scattering combination multiwavelength Brillouin-Raman fiber laser

In this paper we experimentally demonstrate the effect of large effective area fiber length on the performance of a multiwavelength Brillouin–Raman fiber laser in which the forward and backward generated Stokes lines due to Brillouin scattering are combined together through a 3 dB coupler. Thus, the demonstrated laser is dubbed a forward–backward scattering combination multiwavelength Brillouin–Raman fiber laser (FBSC-MBRFL). This laser system utilizes a large effective area fiber and a dispersion compensating fiber that act as Brillouin and Raman gain media, respectively. It is demonstrated that by employing forward pumping schemes, the demonstrated laser system is capable of generating a good flat amplitude Brillouin Stokes line with an average optical to noise ratio of 17 dB along the spectral spans. However, the backward pumping scheme is able to produced high bandwidth spans. At the optimal large effective area fiber length of 50 km, a Raman pump power of 1100 mW at Brillouin pump wavelengths of 1550 mm and 1560 nm is identified to produce the maximum bandwidth with values of approximately 28.45 nm and 24.08 nm, respectively.

All-Optical XOR Logic Gates: Insights and Comparisons

Three XOR photonics logic gate configurations namely semiconductor optical amplifier-Mach Zender interferometer cross phase modulation (SOA-MZI XPM), SOA-MZI cross gain modulation (XGM) and terahertz optical asymmetrical demultiplexer (TOAD) XOR are analysed and compared in terms of generated power, optical signal-to-noise ratio (OSNR) values and bit error rate (BER) signal quality. The highest generated power is possessed by the TOAD at 23.5 dBm, the SOA-MZI XPM showed the most extinction ratio or OSNR with 109.6 dB whereas the best BER is recorded in the SOA-MZI XGM at 4.42 x 10-22.

Fiber Length Optimization of Ring Cavity Multi-Wavelength Brillouin Fiber Laser Utilizing Fiber Bragg Grating

In this paper, we experimentally investigated the performance of ring cavity multi-wavelength Brillouin fiber laser utilizing fiber Bragg grating which operated in the C-band wavelength region. The combination of stimulated Brillouin scattering and selective wavelengths gave a new invention in the optical fiber communication. Five different lengths of single mode fiber are used in order to get the best gain medium for stimulated Brillouin scattering effect. Up to 33 of Brillouin Stokes signals and 31 of anti-Stokes signals were obtained when 10 km fiber length was used in the laser system. The average value optical signal to noise ratio of 15 dB has been achieved. The broadening bandwidth of Brillouin Stokes signals also occurred at the center wavelength of 1550 nm based on the 3 dB bandwidth of 5 nm fiber Bragg grating.

Remazol orange dye sensitized solar cell

Water based Remazol Orange was utilized as the dye sensitizer for dye sensitized solar cell. The annealing temperature of TiO2 working electrode was set at 450 °C. The performance of the device was investigated between dye concentrations of 0.25 mM and 2.5 mM at three different immersion times (3, 12 and 24 hours). The adsorption peak of the dye sensitizer was evaluated using UV-Vis-Nir and the device performance was tested using solar cell simulator. The results show that the performance was increased at higher dye concentration and longer immersion time. The best device performance was obtained at 0.2% for dye concentration of 2.5 mM immersed at 24 hours.

Optimization of Output Coupling Ratio for Multi-Wavelength Brillouin Fiber Laser Employing FBG and DCF as Gain Medium

A ring-cavity multi-wavelength Brillouin fiber laser by employing a fiber Bragg grating and dispersion compensating fiber was experimentally demonstrated. The multi-wavelength Brillouin fiber laser has been analyzed at different output coupling ratios at 1550 nm of Brillouin pump wavelength. A ring-cavity multi-wavelength Brillouin fiber laser has been designed with a 16 km long of dispersion compensating fiber which acts as gain medium for stimulated Brillouin scattering effect. Dispersion compensating fiber is designed to have small core size and has higher nonlinear coefficient. As a result, 8 Brillouin Stokes signals were produced at maximum Brillouin power of 21 dBm and output coupling ratio of 80%. The best performance of output coupling ratio was determined by 70% with the highest of signal to noise ratio at 38.39 dB.