Switchable dual-wavelength erbium-doped fiber-ring laser based on one polarization maintaining fiber Bragg grating in a Sagnac loop interferometer

Switchable dual-wavelength fiber lasers based on a semiconductor optical amplifier and a polarization-maintaining fiber Bragg grating

“…[6][7][8][9][10][11][12] A PMFBG of size about 40 mm, written in a home-made panda polarizationmaintaining and photosensitive fiber ͑PMPF͒ was fabricated using a uniform phase mask ͑with a phase mask period of 1068 nm͒ and KrF excimer laser. The PMPF has a beat length of 4.98 mm at 1550 nm, which corresponds to a wavelength separation of the orthogonally polarized modes of the reflection peak from the PMFBG of about 0.336 nm.…”

“…In the experiment, the wavelength shift was less than 0.01 nm due to the limitation of OSA resolution, and the output power variation was very small ͑less than 0.1 dB͒ under an invariant environment, compared with that of an EDF-based fiber laser with similar configuration. [6][7][8][9][10][11][12] This is because the SOA is characterized by inhomogeneous broadening and can support lasing oscillations at many wavelengths simultaneously in the laser cavity, but an EDF limits the number of lasing modes and induces mode competition because of homogeneous broadening of the erbium ions.…”

“…7 Multiwavelength fiber lasers based on the PMFBG have been deeply studied, and various configurations have been proposed. [6][7][8][9][10][11][12] The semiconductor optical amplifier ͑SOA͒ has the important property of inhomogeneous broadening and can support many wavelengths of lasing oscillation simultaneously in the laser cavity, but an erbium-doped fiber ͑EDF͒ will limit the number of lasing modes because of the homogeneous broadening of erbium ions. Zhao et al and Liu et al realized switchable multiwavelength EDF-ring lasers using a FBG in high-birefringence fiber.…”

“…Thus, we proposed a switchable dual-wavelength EDF-ring laser based on one PMFBG in a Sagnac loop interferometer. 12 However, a fiber laser based on the SOA and PMFBG and whether it can achieve the wavelength-switching function or not have not been studied.…”

Spectral character of polarization-maintaining fiber Bragg grating interrogated by different linearly polarized light

“…This property offers considerable flexibility in the application of the fiber lasers for wavelength selection [1][2][3][4][5] and temperature and strain sensing. Because of the birefringence in the polarization-maintaining fiber (PMF), the grating showed two spectrally separated orthogonally polarized reflection peaks, which correspond to two wavelengths.…”