AdValue Photonics, 3708 East Columbia Street, Suite 100, Tucson, Arizona 85714, USA.
Opt Lett. 2011 Jun 15;36(12):2293-5. doi: 10.1364/OL.36.002293.
We generated single-frequency pulses at kilowatt peak power from an all-fiber Tm-doped master oscillator power amplifier system, which is the first report of this kind (to the best of our knowledge) of a laser in the 2 μm region. Compared with the laser linewidth of seed pulses, spectral broadening by a factor of 3 was observed with the amplified pulses. This was attributed to self-phase modulation in passive pigtail fibers of the components (isolator and wavelength division multiplexing) that were placed after the fiber amplifier. The short pulse width (~7 ns) of the kilowatt-level pulses prevents an onset of stimulated Brillouin scattering in the long fiber. When launching the pulses into several-meter single-mode fiber, significant nonlinear spectral broadening occurs due to modulation instability in the fiber. This reaction is beneficial for generation of a mid- and long-wavelength IR supercontinuum in nonlinear IR fibers.
我们从全光纤掺铥主振荡器功率放大器系统中产生了千瓦峰值功率的单频脉冲，这是（据我们所知）在 2 μm 区域内的第一台此类激光器。与种子脉冲的激光线宽相比，放大后的脉冲观察到光谱展宽了 3 倍。这归因于光纤放大器之后放置的组件（隔离器和波分复用器）的无源尾纤中的自相位调制。千瓦级脉冲的短脉冲宽度（约 7 ns）可防止长光纤中受激布里渊散射的发生。当将脉冲发射到数米长的单模光纤中时，由于光纤中的调制不稳定性，会发生显著的非线性光谱展宽。这种反应有利于在非线性红外光纤中产生中长波长红外超连续谱。
