Compact and efficient O-band bismuth-doped phosphosilicate fiber amplifier for fiber-optic communications

Abstract

During last decades there has been considerable interest in developing a fiber amplifier for the 1.3-$$\upmu $$μm spectral region that is comparable in performance to the Er-doped fiber amplifier operating near 1.55 $$\upmu $$μm. It is due to the fact that most of the existing fiber-optic communication systems that dominate terrestrial networks could be used for the data transmission in O-band (1260–1360 nm), where dispersion compensation is not required, providing a low-cost increase of the capacity. In this regard, significant efforts of the research laboratories were initially directed towards the study of the praseodymium-doped fluoride fiber amplifier having high gain and output powers at the desired wavelengths. However, despite the fact that this type of amplifiers had rapidly appeared as a commercial amplifier prototype it did not receive widespread demand in the telecom industry because of its low efficiency. It stimulated the search of novel optical materials for this purpose. About 10 years ago, a new type of bismuth-doped active fibers was developed, which turned out to be a promising medium for amplification at 1.3 $$\upmu $$μm. Here, we report on the development of a compact and efficient 20-dB (achieved for signal powers between $$-40$$-40 and $$-10$$-10 dBm) bismuth-doped fiber amplifier for a wavelength region of 1300–1350 nm in the forward, backward and bi-directional configurations, which can be pumped by a commercially available laser diode at 1230 nm with an output power of 250 mW. The compactness of the tested amplifier was provided by using a depressed cladding active fiber with low bending loss, which was coiled on a reel with a radius of 1.5 cm. We studied the gain and noise figure characteristics at different pump and signal powers. A record gain coefficient of 0.18 dB/mW (at the pump-to-signal power conversion efficiency of above 27$$\%$$%) has been achieved.

Self-Powered, Broadband Photodetector Based on Two-Dimensional Tellurium-Silicon Heterojunction

“…The photodetector demonstrated high photosensitivity over a broadband of wavelengths from 365 to 1300 nm with reproducible and stable photoresponse. The strong photoresponse at 1300 nm implies that it can be used for O-band fiber optic in optical communication applications . The following expressions are used to evaluate a photodetector performance: external 0.25em quantum 0.25em efficiency 0.25em ( EQE ) = h c R e λ responsivity 0.25em ( R ) = | I ph / false( P × S false) | photocurrent 0.25em ( I ph ) = I normall − I normald detectivity 0.25em ( D * ) = S 1 / 2 R false( 2 e I normald false) 1 / 2 where e , c , and h are the electron charge constant, speed of light, and Planck’s constant, respectively, and I d and I l are the dark current and light-on current, respectively.…”

“…The strong photoresponse at 1300 nm implies that it can be used for O-band fiber optic in optical communication applications. 25 The following expressions are used to evaluate a photodetector performance: 26 hcR e external quantum efficiency (EQE) = (1)…”

“…The strong photoresponse at 1300 nm implies that it can be used for O-band fiber optic in optical communication applications. 25 The following expressions are used to evaluate a photodetector performance: 26 where e , c , and h are the electron charge constant, speed of light, and Planck’s constant, respectively, and I d and I l are the dark current and light-on current, respectively. The wavelength, light intensity, and effective area are λ, P , and S (∼24 μm 2 ), respectively.…”

Ultrafast Modulation of THz Waves Based on MoTe2-Covered Metasurface

“…Our work provides a new candidate for on-chip devices on 6G communication, as well as an extraordinary slow light device to be applied in nonlinear optics, optical storage, and so on. The indirect band gap of MoTe 2 implies a possible application for near-infrared fiber communication located at the O-band (1260 nm–1360 nm) [ 58 ], enabling a hybrid control and ultrafast trigger of the infrared and THz waves. Furthermore, recent advances of the optically controlled THz metasurface have experimentally demonstrated a calibration-free sensor for achieving high-precision biosensing detection [ 31 ].…”

Low-Frequency Noise Characteristics of (Al, Ga)As and Ga(As, Bi) Quantum Well Structures for NIR Laser Diodes

“…Laser diodes (LDs) nowadays are widely used in the communication, scientific, and medicine fields and other applications, not only as an effective source for solid-state laser pumping, where signal-to-noise ratio is important [ 1 , 2 ], or as a light source in fiber systems [ 3 ], but also in wireless optical communication systems including visual light communication systems, where coherent light is employed as an information carrier [ 2 , 3 ]. The infrared (IR) spectral region is rich in organic and often harmful molecule footprints, such as methane, carbon dioxide, nitrogen, etc.…”