Crystallization behavior of the glass system AlF3-MgF2-CaF2-SrF2-BaF2-YFa-TeO2 （AMCSBY-TeO2） was studied by the nonisothermal method using differential thermal analysis. The activation energy E and Avrami exponent g...Crystallization behavior of the glass system AlF3-MgF2-CaF2-SrF2-BaF2-YFa-TeO2 （AMCSBY-TeO2） was studied by the nonisothermal method using differential thermal analysis. The activation energy E and Avrami exponent g were determined by nonisothermal method. It is found that the value of E varies with increasing TeO2 and reaches a minimum at 10 mol fraction TeO2, while g decreases from 3.65 to 1.78 with the addition of TeO2. X-ray diffraction shows that Ba2TeaOs, MgTe205, and SrTeOa phase formed when the glasses were reheated. The addition of TeO2 changes the crystallization mechanism and improves the stability of the fluoroaluminate glass.展开更多
High flatness, wide bandwidth, and high-coherence properties of supercontinuum(SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, sin...High flatness, wide bandwidth, and high-coherence properties of supercontinuum(SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, since special dispersion profiles are required, especially when pump pulses with duration over 100 fs are employed. We propose an all-solid microstructured fiber composed only of hexagonal glass elements. The optimized fiber possesses an ultraflat all-normal dispersion profile, covering a wide wavelength interval of approximately 1.55 μm. An SC spectrum spanning from approximately 1030 to 2030 nm(corresponding to nearly one octave) with flatness<3 dB is numerically generated in the fiber with 200 fs pump pulses at 1.55 μm. The results indicate that the broadband ultraflat SC sources can be all-fiber and miniaturized due to commercially achievable 200-fs fiber lasers. Moreover, the SC pulses feature high coherence and a single pulse in the time domain, which can be compressed to 13.9-fs pulses with high quality even for simple linear chirp compensation. The Fourier-limited pulse duration of the spectrum is 3.19 fs, corresponding to only 0.62 optical cycles.展开更多
文摘Crystallization behavior of the glass system AlF3-MgF2-CaF2-SrF2-BaF2-YFa-TeO2 （AMCSBY-TeO2） was studied by the nonisothermal method using differential thermal analysis. The activation energy E and Avrami exponent g were determined by nonisothermal method. It is found that the value of E varies with increasing TeO2 and reaches a minimum at 10 mol fraction TeO2, while g decreases from 3.65 to 1.78 with the addition of TeO2. X-ray diffraction shows that Ba2TeaOs, MgTe205, and SrTeOa phase formed when the glasses were reheated. The addition of TeO2 changes the crystallization mechanism and improves the stability of the fluoroaluminate glass.
基金National Natural Science Foundation of China(NSFC)(61475171,11374084,61705244,61307056)Natural Science Foundation of Shanghai(17ZR1433900,17ZR1434200)
文摘High flatness, wide bandwidth, and high-coherence properties of supercontinuum(SC) generation in fibers are crucial in many applications. It is challenging to achieve SC spectra in a combination of the properties, since special dispersion profiles are required, especially when pump pulses with duration over 100 fs are employed. We propose an all-solid microstructured fiber composed only of hexagonal glass elements. The optimized fiber possesses an ultraflat all-normal dispersion profile, covering a wide wavelength interval of approximately 1.55 μm. An SC spectrum spanning from approximately 1030 to 2030 nm(corresponding to nearly one octave) with flatness<3 dB is numerically generated in the fiber with 200 fs pump pulses at 1.55 μm. The results indicate that the broadband ultraflat SC sources can be all-fiber and miniaturized due to commercially achievable 200-fs fiber lasers. Moreover, the SC pulses feature high coherence and a single pulse in the time domain, which can be compressed to 13.9-fs pulses with high quality even for simple linear chirp compensation. The Fourier-limited pulse duration of the spectrum is 3.19 fs, corresponding to only 0.62 optical cycles.
