RESUMO
Here, we demonstrate a compact and efficient high-power mid-infrared supercontinuum (MIR-SC) laser source based on a tunable noise-like pulse (NLP) fiber laser system and a short section of single-mode germania-core fiber (GCF). The NLP all-polarization-maintaining fiber laser system can deliver the maximum output power of â¼30.6 W and a broadband spectrum (â¼1.8-2.7 µm) with a compact single-stage fiber amplifier. By directly pumping only â¼6.5 cm-long GCF with a core diameter of â¼3.5 µm, a MIR-SC (spectral coverage of â¼1.5-3.3 µm) with a maximum power of â¼25.2 W and a power conversion efficiency â¼81.2% is obtained, which represent the highest power and efficiency in any single-mode GCF-based MIR-SCs, to the best of our knowledge. Our study contributes to the high-power MIR-SC laser source with compact all-fiber configuration, and will prompt its practical applications.
RESUMO
In this paper, we demonstrate a simplified one-to-many scheme for efficient mid-infrared (MIR) parametric conversion. Such a scheme is based on a continuous wave (CW) single longitudinal mode master oscillator power-amplifier (MOPA) fiber system as the signal source and a picosecond pulsed MOPA fiber system, exhibiting multiple longitudinal modes, as the pump source. The signal and pump beams are combined and co-coupled into a piece of 50-mm long 5% MgO-doped PPLN crystal for the parametric conversion. As high as â¼3.82 W average power at a central idler wavelength of â¼3.4â µm is achieved when the launched pump and signal powers are â¼41.73 and â¼11.45 W, respectively. Above some threshold value, the delivered idler power shows a roll-over effect against the signal power and saturation-like effect against the pump power. Consequently, the highest conversion efficiency is observed at such a threshold pump power. To the best of our knowledge, our result represents the highest average power produced from any single-pass parametric conversion source with >3â µm idler wavelength feeding with a CW signal. Moreover, our proposed scheme can simplify the design of parametric conversion system significantly and meanwhile make the system more robust in applications. This is attributed to two main aspects. Firstly, the scheme's one-to-many feature can reduce wavelength sensitivity remarkably in the realization of quasi-phase-matching. Secondly, for moderate power requirement it does not always require a high peak power synchronized pulsed signal source; a CW one can be an alternative, thereby making the system free from complex time synchronization and the related time jitter.
RESUMO
Herein, we presented a high energy noise-like (NL) pulse Tm-doped fiber laser (TDFL) system. Relying on the nonlinear amplifying loop mirror (NALM), stable noise-like pulses with coherence spike width of â¼317 fs and envelope width of â¼4.2â ns were obtained from an all polarization-maintaining fiberized oscillator at central wavelength of â¼1946.4â nm with 3â dB bandwidth of â¼24.9â nm. After the amplification in an all-fiberized TDF amplifier system, the maximum average output power of â¼32.8 W and pulse energy of â¼10.1 µJ were obtained, which represents the highest pulse energy of NL pulse at â¼2 µm, to the best of our knowledge. We believe that the high energy NL pulse source has the potential application in mid-infrared supercontinuum generation.