The optical wave breaking (OWB) characteristics in terms of the pulse shape, spectrum, and frequency chirp, in the normal dispersion regime of an optical fiber with both the third-order dispersion (TOD) and quinti...The optical wave breaking (OWB) characteristics in terms of the pulse shape, spectrum, and frequency chirp, in the normal dispersion regime of an optical fiber with both the third-order dispersion (TOD) and quintic nonlinearity (QN) are numerically calculated. The results show that the TOD causes the asymmetry of the temporal- and spectral-domain, and the chirp characteristics. The OWB generally appears near the pulse center and at the trailing edge of the pulse, instead of at the two edges of the pulse symmetrically in the case of no TOD. With the increase of distance, the relation of OWB to the TOD near the pulse center increases quickly, leading to the generation of ultra-short pulse trains, while the OWB resulting from the case of no TOD at the trailing edge of the pulse disappears gradually. In addition, the positive (negative) QN enhances (weakens) the chirp amount and the fine structures, thereby inducing the OWB phenomena to appear earlier (later). Thus, the TOD and the positive (negative) QN are beneficial (detrimental) to the OWB and the generation of ultra-short pulse trains.展开更多
The supercontinuum (SC) generation in all-normal dispersion (ANDi) photonic-crystal fiber (PCF) pumped by high power picosecond pulses are investigated in this paper. Our results show that an octave SC may be ac...The supercontinuum (SC) generation in all-normal dispersion (ANDi) photonic-crystal fiber (PCF) pumped by high power picosecond pulses are investigated in this paper. Our results show that an octave SC may be achieved by pumping the ANDi PCF with picosecond pump pulses. However, the PCF length required may have to be lengthened to several tens of centimeters, which is much longer than that with femtosecond pump pulses. The relatively long PCF gives rise to much higher Raman gain and stronger Raman frequency shift compared to those with femtosecond pump pulses, which in turn not only cause a distorted temporal waveform and an un-flattened spectrum, but also severely degrade the coherence of the generated SC.展开更多
基金supported by the Postdoctoral Fund of China(Grant No.2011M501402)the National Natural Science Foundation of China(Grant No.61275039)+2 种基金the 973 Program of China(Grant No.2012CB315702)the Key Project of the Chinese Ministry of Education,China(Grant No.210186)the Major Project of the Natural Science Foundation supported by the Educational Department of Sichuan Province,China(Grant Nos.13ZA0081 and 12ZB019)
文摘The optical wave breaking (OWB) characteristics in terms of the pulse shape, spectrum, and frequency chirp, in the normal dispersion regime of an optical fiber with both the third-order dispersion (TOD) and quintic nonlinearity (QN) are numerically calculated. The results show that the TOD causes the asymmetry of the temporal- and spectral-domain, and the chirp characteristics. The OWB generally appears near the pulse center and at the trailing edge of the pulse, instead of at the two edges of the pulse symmetrically in the case of no TOD. With the increase of distance, the relation of OWB to the TOD near the pulse center increases quickly, leading to the generation of ultra-short pulse trains, while the OWB resulting from the case of no TOD at the trailing edge of the pulse disappears gradually. In addition, the positive (negative) QN enhances (weakens) the chirp amount and the fine structures, thereby inducing the OWB phenomena to appear earlier (later). Thus, the TOD and the positive (negative) QN are beneficial (detrimental) to the OWB and the generation of ultra-short pulse trains.
基金the National High Technology Research and Development Program of China(Grant No.2011AA030203)the National Natural Science Foundation of China(Grant No.61250017)the Key Research Program of the Chinese Academy Sciences(Grant No.KJZD-EW-W02)
文摘The supercontinuum (SC) generation in all-normal dispersion (ANDi) photonic-crystal fiber (PCF) pumped by high power picosecond pulses are investigated in this paper. Our results show that an octave SC may be achieved by pumping the ANDi PCF with picosecond pump pulses. However, the PCF length required may have to be lengthened to several tens of centimeters, which is much longer than that with femtosecond pump pulses. The relatively long PCF gives rise to much higher Raman gain and stronger Raman frequency shift compared to those with femtosecond pump pulses, which in turn not only cause a distorted temporal waveform and an un-flattened spectrum, but also severely degrade the coherence of the generated SC.