We investigate a high-pumping-efficiency and linewidth-broadening, L-band, erbium-doped, superfluorescent fiber source (SFS) using a cascaded dual-backward-pumped configuration. With optimized structural parameters, the design provides an L-band SFS with a mean wavelength of 1578.2 nm, an output power of 132.8 mW, and a spectral linewidth of 52.6 nm without using any external spectral filters under 265-mW pump power. The high pumping efficiency of 50.1% is achieved experimentally. The design relaxes the danger in resonant lasing while enhancing the pumping efficiency and broadening the linewidth.
We first demonstrate that by inserting an appropriate section of unpumped erbium-doped fiber (EDF) in an erbium-doped superfluorescent fiber source (SFS) of double-pass backward configuration, a stable L-band SFS can be achieved. The fiber-length arrangement of unpumped fiber are shown to have significant effects on the output properties of the L-band SFS. The spectral linewidth is broadened, and the variation of mean wavelength versus pump power is eliminated to achieve a wideband and mean wavelength stable L-band SFS by optimizing the fiber-length ratio of the pumped fiber length to the total fiber length. For a 19-m-long total EDF with fiber-length ratio of 0.84, a mean wavelength stable L-band SFS with a spectral linewidth of 49.6 nm, an output power of 46.3 mW, and a mean wavelength of 1583.20 nm was experimentally achieved.
Two interleavers with potential applications for dense wavelength division multiplexing (DWDM) system are designed
based on the analysis of the phase characteristic of Gires-Tournois resonator. One has only one G-T resonator and the
other has two. The performance of the two interleavers has been compared .We find the latter is better than the former
and an Interleaver of a channel spacing of 50GHz, ripple less than 0.05dB, a -0.5dB passband of 23.4GHz (46.8% of the
spacing), a-30dB stopband of 20.8GHz (41.6% of the spacing), and a channel isolation of -33.95dB is obtained.
In this paper, a simple single-backward configuration with a section of un-pump fiber is presented to achieve a stable
L-band superfluorescent fiber source (SFS). The effects of the structural parameters on the output characteristics of the
L-band SFS in terms of output spectrum, mean wavelength, and linewidth are theoretically examined. By selecting
suitable structure parameters, an L-band SFS with mean wavelength insensitive to pump power is achieved under a
pump power of 190mW, corresponding to a mean wavelength of 1583.20nm, an output power of 47mW, and a spectral
linewidth of 49.6nm. The proposed L-band SFS design shows its tremendous advantages as simple structure and good
performances that make it be useful in WDM system, fiber optic gyroscopes and fiber sensor systems applications.
We have experimentally investigated a new two-stage C+L-band (1525 to 1605-nm) amplified spontaneous emission (ASE) fiber source using a dual forward pumping configuration. The proposed source offers a high pumping efficiency of 24.6%, output power of about 52 mW, and a wide bandwidth of 80 nm. Without using any external spectral filters, the source has a low spectral ripple between 2.4 and 2.9 dB for different pumping power levels. This designed configuration is also suitable for high-efficiency L-band ASE. The obtained source will be useful in characteristic measurement for wavelength-division multiplexing components and spectrum-sliced multiwavelength fiber sources for local access networks.
We present a two-stage dual-forward pumped configuration to achieve a wavelength stable L-band amplified
spontaneous emission (ASE) source. The effects of EDF length and pump power arrangements on the characteristics of
L-band ASE spectrum, output power, and mean wavelength are investigated. The results show that not only the pumping
conversion efficiency can be improved largely but also the pump power independent mean wavelength operation can be
achieved by optimizing the fiber length ratio and pump ratio of the dual-forward pumped configuration as comparing to
that of the conventional double-pass forward configuration.
Two kinds of configurations of L-band amplified spontaneous emission (ASE) source with two-stage EDF and dual
forward pumps are suggested for generating a high power L-band ASE spectrum. The characteristics are theoretically
compared in terms of the output power, pumping conversion efficiency, bandwidth, and mean wavelength stability for
these two configurations. The EDF length and pump power allotment are also optimized. An L-band ASE source of
76mW output power with about 36.2% pumping conversion efficiency are experimentally obtained.
Two novel methods are demonstrated to build up a band-selective amplified spontaneous emission (ASE) broadband light source that can operate in the selective conventional band (C-band, 1525~1565 nm) or long-wavelength band (L-band, 1565~1605 nm) region using a 1×2 optical switch. With the backward ASE feedback technique, an output power of 27.6 mW for the C-band ASE and 11.8 mW for the L-band ASE are obtained while with the compound pump technique, a power of 24.5 mW for L-band ASE and 27.2 mW for C-band ASE are obtained both with a fixed total pump power of 100 mW. The advantage of using the backward ASE feedback technique is that the ASE source design is simpler whereas the power of L-band ASE is lower, and the notable advantage of using the compound pump technique is that the output powers of the two selective bands (C- or L-band) are balanced though the configuration is a little complicated.
A scheme for generating multi-wavelength fiber source based on erbium-doped fiber amplified spontaneous emission and spectrum sliced technique is demonstrated for potential applications in the dense-wavelength division multiplexing (DWDM) communication systems. A spectrum sliced multi-wavelength fiber source of 140 channels (extinction ratios larger than 13 dB) with 0.57nm channel spacing covering C-band and L-band is obtained by optimizing the erbium-doped fiber length and the pumping ratio of the scheme.
In this paper, a practical two-stage scheme is suggested for generating a C+L-band erbium-doped fiber amplified spontaneous emission (ASE) broadband light source. A considerable power increase of the L-band ASE spectrum is achieved by injecting the C-band ASE into the long section erbium-doped fiber. The C+L-band ASE source is obtained by combining the enhanced L-band ASE with the C-band ASE from two stages respectively. A spectrum flat ASE source with nearly 80nm bandwidth and about 15.9dBm output power is obtained with a total pump power of 180mW. Namely, the pump conversion efficiency is about 21.6%. Such a broadband incoherent light source is desirable for various applications in some areas like sliced wavelength- division multiplexed local-access networks, characteristic measurement for dense wavelength-division multiplexed components, and fiber-optic sensor systems etc.
In this paper, a novel scheme for band selection in an amplified spontaneous emission source (ASE) based on erbium-doped fiber is demonstrated. C-band operation is obtained without backward ASE feedback whereas L-band operation is obtained with backward ASE feedback with the used of a 1X2 optical switch. A selective ASE source with an output power of 27.6mW for the C-band and 11.8mW for the L-band is obtained experimentally with a total pump power of 100mW of 1480nm laser diode. This band selective ASE source convenience the users select the necessary band when needed without any form of upgrading or additional module attachment therefore has the potential use for the dual-band DWDM device characterization and metro networks.
A new bidirectional pumped configuration for an L-band erbium-doped superfluorescent fiber source is demonstrated. Data are presented showing that with this configuration, the mean wavelength variation with the pump power can be reduced to zero by optimizing the fiber length and the pumping ratio of forward to total pump power.
A novel one-stage configuration for high stability L-band (1565-1605nm) erbium-doped superfluorescent fiber source (SFS) is designed and investigated. The superfluorescent source is realized in a 19m erbium-doped fiber with double-pass bi-directional pumping configuration. High pumping conversion efficiency and pump power insensitive mean wavelength characteristic due to the bi-directional pumping configuration. Pumping conversion efficiency about 60% and flat spectral linewidth over 30 nm is obtained by the proposed SFS.