Single-frequency bismuth-doped fiber power amplifier at 1651 nm

Abstract

Erbium doped fiber amplifiers play an important role in various applications, spanning from fiber communication to optical sensing. Unfortunately, their gain bandwidth is limited to telecom C-and L-bands (from 1530-1625 nm). The application of bismuth-doped fibers is a promising approach for optical signal amplification at longer wavelengths. In this paper, a bismuth-doped fiber power amplifier seeded with a 1651 nm single-frequency laser diode is presented and its performance is experimentally analyzed. This amplifier may be used to improve performance of systems for methane detection, e.g. those based on photoacoustic spectroscopy or in remote/stand-off configuration (methane has a molecular absorption line near to 1651 nm). Two configurations of the amplifier are demonstrated and in both cases an output power of more than 80 mW is obtained. Limitations of current design are discussed. The obtained results give good a perspective for simple and compact fiber amplifiers with output powers exceeding 100 mW in the spectral region of ~1630-1750 nm.

Operation of a Single-Frequency Bismuth-Doped Fiber Power Amplifier near 1.65 µm

“…For a longer wavelength (i.e., 1687 nm), the measured power was even higher: 197 mW (or 22.94 dBm) when a seed power of 5.48 mW was used. These results are almost two times better than those demonstrated previously (87 mW at 1651 nm in [21] and 107 mW at 1687 nm in [22]). The measured gain (shown in Figure 5c) varied from 26 dB (for a low input power at 1687 nm) to approximately 10 dB (for a high input power at 1651 nm).…”

“…A schematic of the BDFA is shown in Figure 1. A 90 m-long germanosilicate BDF was used as an active fiber (the same fiber was also used in our previous works [21,22]). The GeO 2 content of the fiber was ~50 mol.%.…”

“…This paper presents a continuation of our earlier experiments, in which the performance of a bismuth-doped fiber amplifier (BDFA) at 1651 [21] and 1687 nm [22] was analyzed. Previously, the output powers of ~87 and ~107 mW were obtained at 1651 and 1687 nm, respectively.…”

“…These results were limited by two issues. The first was stimulated Brillouin scattering (SBS) in BDF, which turned out to affect the BDFA gain when high pumping powers were used [21]. The other issue was the efficiency of coupling the signal (at 1651 or 1687 nm) and the pump (at 1550 nm).…”

Development of Bismuth-Doped Fibers (BDFs) in Optical Communication Systems

“…BDFs have many applications in different optical systems because of their wavelength based discriminative transmission losses [41]. A 1651 nm single-frequency laser diode is providing with a Bi-doped fiber power amplifier, and its performance is evaluated experimentally [42]. This amplifier is using to increase the performance of methane detection systems, such as remote stand-off systems or photoacoustic spectroscopy (methane has a molecular absorption line of almost 1651 nm).…”