Enhanced multiwavelength generation in Brillouin fiber laser with pump noise suppression technique

A new multiwavelength Brillouin fiber laser (BFL) that provides a large number of Stokes lines with improved optical signal-to-noise ratio has been proposed and demonstrated. The BFL cavity is only formed by a nonlinear fiber loop mirror (NOLM) with 500 m long highly nonlinear fiber (HNLF). The BFL with improved performance is based on the suppression of the Brillouin pump noise floor utilizing a narrow tunable bandpass filter. The generation of Stokes lines covering up to a 33.67 nm wavelength range is achieved by setting the Brillouin pump signal within the HNLF's zero dispersion wavelength and with power of 250 mW. This is owing to the combination of the stimulated Brillouin scattering and four-wave mixing effect in the NOLM structure

Flat amplitude and wide multiwavelength Brillouin/erbium fiber laser based on Fresnel reflection in a micro-air cavity design

In this report, we demonstrate a wide multiwavelength Brillouin-erbium fiber laser (MBEFL) with improved flatness that integrates a micro-air cavity. This air-gap introduces a cavity loss to overcome the gain saturation as well as providing efficient pump recycling scheme through Fresnel back-reflection. In addition, the efficient four-wave mixing in the highly nonlinear fiber contributes to the self-flattening of the output spectra. During operation, the optimized pumping values are set at 13 dBm Brillouin power and 600 mW erbium-ytterbium doped fiber amplifier when the air-gap length is fixed at 10 µm. A total of 180 Stokes lines are produced with a channel spacing of 0.08 nm. The flat lasing bandwith is 14 nm that consists of 1557 to 1571 nm wavelengths within 3-dB span. The average optical signal-to-noise ratio is 18 dB, having high peak power of −8 dBm. To our knowledge, this is the best result attained in MBEFLs with respect to the spectral flatness. In fact, the power stability of 0.76 dB order over 45 minute durations merits it applications in optical fiber sensing and communications

Stable multiwavelength thulium fiber laser assisted by four wave mixing effect

In this work, stable multiwavelength thulium laser (TDFL) using interleaving filter and assisted by four wave mixing (FWM) effect in 0.5 km long highly nonlinear fiber (HNLF) is experimentally demonstrated. The impacts of altering the thulium pump power and wavelength on several laser characteristics such as threshold, laser count, output power and optical signal to noise ratio are investigated. Up to 19 output wavelengths within a 10 dB bandwidth with optical signal-to-noise ratio of more than 35 dB were generated from 1875 nm to 1897 nm. The laser has a threshold pump power of 0.3 W and a maximum peak power and wavelength fluctuations within 60 min of 1 dB and 0.2 nm respectively, which indicates the good stability of the proposed fiber laser. The laser performance without HNLF emphasizes the significant role of FWM in the performance of TDFL in terms of stability and number of wavelengths

150-channel four wave mixing based multiwavelength Brillouin-erbium doped fiber laser

A wide band tunable multiwavelength Brillouin-erbium fiber laser (BEFL) is developed. In this structure, the laser is formed between a double pass amplification box and a highly nonlinear fiber (HNLF), which acts as a virtual mirror, results in removing the reflective physical mirror from one side of the laser structure. A large number of Stokes and anti-Stokes lines are generated through cascading stimulated Brillouin scattering and inducing four wave mixing process inside the HNLF. Due to optimizing Brillouin and erbium doped fiber (EDF) pump powers, the Rayleigh back scattering is efficiently suppressed, and the generated BEFL wavelengths are free from self lasing cavity modes over a wide tuning range. At EDF pump power and Brillouin pump power of 100 mW and 3 dBm, respectively, up to 150 Stokes lines with wavelength spacing of 0.076 nm, and a tuning range of 40 nm were achieved

Simple multiwavelength Brillouin-Erbium-doped fiber laser structure based on short SSMF

An efficient multiwavelength Brillouin–Erbium fiber laser (BEFL) was developed by improving the feedback mechanism of Brillouin Stokes lines. The BEFL performance in terms of threshold power and wavelengths count was improved by using a new structure of double pass amplification cavity. The new structure utilized the variable optical coupler (VOA) not only as the input and output ports but also to form a fiber loop mirror that reduces the number of optical components, thus, only three optical components were needed. By optimizing the Brillouin and 1480 nm pump power, up to 41 channels and 26 channels were obtained using 0.6 km and 0.3 km long of standard single mode fiber (SSMF), respectively

A stabilized tunable dual wavelength erbium-doped fiber laser with equal output power

Tunable dual-wavelength erbium-doped fiber laser with good stability is experimentally demonstrated. Output power of as high as +5.26 dBm is obtained in dual ring configuration. Both laser output can be tuned to as closed as 0.8 nm spacing between each other, with tuning range of 31.33 nm. The stability of both outputs was tested that results in less than ±0.8 dB and ±0.01 nm in power and wavelength fluctuation, respectively

The framework and analysis tool to evaluate the effect of product design to the performance of manufacturing system

Modeling of a manufacturing system enables one to identified the effects of key design parameters on the system performance d as a result to make correct decision. This paper proposes a manufacturing system modeling approach using a mathematical model approach based on real data porn a selected company, Ciriri Tegap Sdn. Bhd The model was used to improve the existing system utilization in relation to product design and system performance. The model incoyorates few parameters mch as utilization, cycle time, throughput, and batch size. The study also showed that the validity of developed model is good enough to apply and the maximum value of relative error is 30%, just below the limit value 32%. Iherefore, the nzodel developed in this study is a valuable alternative model in evaluating a manufacturing system

Dual-wavelength thulium-doped fiber laser assisted by non-adiabatic tapered fiber

MUHAMMAD HAFIZ BIN ABU BAKAR/// NADIAH HUSSEINI BINTI ZAINOL ABIDIN,MOHD ADZIR BIN MAHDI/// Al-Alimi, A.W,Abas, A.F,Alresheedi, M.T

Half-linear cavity multiwavelength Brillouin-erbium fiber laser

Multiwavelength half-linear cavity Brillouin erbium fiber laser (BEFL) has been demonstrated. The half-linear cavity BEFL is formed by utilizing only two circulators: one circulator acts as input and output ports and the other circulator is used to form a physical mirror. This design exhibits low peak power difference between the adjacent channels, which is about 0.8 dB. At Brillouin pump (BP) power of 5 dBm and erbium doped fiber (EDF) pump power of 90 mW, up to 19 channels over a wide range of 40 nm (1529 nm to 1569 nm) have been obtained. These channels are free from self lasing cavity modes and for the first twelve Stokes lines, the optical signal to noise ratio (OSNR) is approximately higher than 20 dB

Nonlinear fiber loop mirror optimization to enhance the performance of multiwavelength brillouin/erbium-doped fiber laser

The performance of multiwavelength BEFL based on nonlinear fiber loop mirror (NOLM) optimization has been experimentally investigated. The NOLM is optimized to act as highly reflective mirror, which results in reducing the threshold power and enhancing the number of the generated Stokes lines at low EDF pump power as well. This design presents a low threshold power of 2 mW and generates up to 26 Stokes lines at EDF pump power of 25 mW