A high-power all-fiber single-frequency polarization-maintained(PM)laser operating at 1 083 nm is demonstrated using a master oscillator power amplifier(MOPA)structure.The seed source of this MOPA laser system is an in-house-built ring-cavity fiber oscillator.Four-stage amplification configuration is employed, in which the maximal output power of the main amplifier is 90.4 W,corresponding to a conversion efficiency of 72.5%.The polarization extinction ratio of the output light is 13 dB.The amplified spontaneous emission is suppressed by a factor of over 25 dB,and no stimulated Brillouin scattering effect is observed when a large-mode-area and high absorption coefficient PM gain fiber is employed.
We demonstrate two self-injection locking extended cavity diode lasers(ECDLs)using resonant optical feedback independently from s-and p-polarizations of a monolithic folded Fabry–Perot confocal cavity(MFC).The relative frequency shift of adjacent axial modes of s resonance and p resonance of MFC is around 1.030 GHz.Beat note measurements between the two ECDLs are performed and present a relative linewidth of 4 kHz.With the help of a narrow-linewidth reference laser,the linewidth of s-component and p-component ECDLs are measured to be about 32 kHz and 40 kHz,respectively.