Selectable dual-wavelength erbium-doped fiber laser with stable single-longitudinal-mode utilizing eye-type compound-ring configuration

Switchable dual-wavelength single-longitudinal-mode erbium fiber laser utilizing a dual-ring scheme with a saturable absorber

“…To generate the multi-wavelength in the EDF-based laser scheme, several techniques have been proposed, such as using a birefringence mechanism in the laser cavity [6], cooling the EDF to mitigate homogeneous broadening [7], applying a frequency shift into the laser cavity [8], and utilizing a hybrid Brillouin-erbium amplifier as the gain medium [9]. However, due to the homogeneous broadening together with the mode hopping of the EDF at room temperature and a longer fiber cavity length, the traditional EDF-based laser produces unstable multilongitudinal-mode (MLM) output [10,11]. Thus, to overcome and suppress the unstable MLM oscillation, the utilization of a saturable absorber (SA), a multiple-ring configuration, the optical injection technique, and a narrow-band filter inside fiber laser cavity has been proposed and demonstrated [12,[10][11][12][13][14].…”

“…However, due to the homogeneous broadening together with the mode hopping of the EDF at room temperature and a longer fiber cavity length, the traditional EDF-based laser produces unstable multilongitudinal-mode (MLM) output [10,11]. Thus, to overcome and suppress the unstable MLM oscillation, the utilization of a saturable absorber (SA), a multiple-ring configuration, the optical injection technique, and a narrow-band filter inside fiber laser cavity has been proposed and demonstrated [12,[10][11][12][13][14].…”

Switchable 10 nm-spaced dual-wavelength SLM fiber laser with sub-kHz linewidth and high OSNR using a novel multiple-ring configuration

“…In one method, an ultra-narrow band-pass filter with two transmission channels is inserted into the laser cavity, such as a chirped moiré fiber Bragg grating (FBG) filter [6], phaseshifted FBG filter [7], or FBG Fabry-Pérot filter [8]. In the other method, common mode-restricting elements with two band-passes or two reflection peaks combined with a saturableabsorber-based auto-tracking filter [2] or compound cavity structure [3,9,10] are used. FBG-based ultra-narrow band-pass filters generally limit the wavelength spacing to a small value, while the second method can enable an EDFL with large wavelength spacing.…”

“…In [2], a dual-wavelength SLM fiber laser with a spacing as wide as 13.2 nm was proposed; this utilized an unpumped EDF saturable absorber and a U-bending-type mode-restricting element composed of two uniform FBGs. A dual-wavelength SLM EDFL with a maximal wavelength spacing of 30 nm, based on an eye-type compound-ring scheme and using two tunable band-pass filters, was reported in [10]. In our previous work [3], 9.96 nm wavelength spacing was achieved for stable dual-wavelength lasing by using two superimposed FBGs (SI-FBGs) as a single compact mode-restricting element and a special subring cavity in the laser system.…”

Utilizing a silicon-photonic micro-ring-resonator and multi-ring scheme for wavelength-switchable erbium fiber laser in single-longitudinal-mode

“…A stable and wavelength-selectable erbium-doped fiber (EDF) ring laser is an attractive light source for applications such as optical fiber sensing, optical testing, microwave photonics, wavelength-division-multiplexing (WDM) transmission, and optical instrument testing [1][2][3][4]. Generally, in order to accomplish the wavelength lasing and tuning, the fiber Fabry-Perot tunable filter (FP-TF), tunable bandpass filter (TBF), and variable fiber Bragg grating (FBG) have been proposed and utilized inside the fiber-loop cavity [5][6][7].…”