Eutectic Bi/MnBi magnetic alloy was prepared by directional solidification.When the growth rate,R>2 cm/h,the MnBi fibre spacing,λ,distributed homogeneously in Bi matrix,follows λ~2R=constant.The thermal gradient....Eutectic Bi/MnBi magnetic alloy was prepared by directional solidification.When the growth rate,R>2 cm/h,the MnBi fibre spacing,λ,distributed homogeneously in Bi matrix,follows λ~2R=constant.The thermal gradient.G_L,does not influence λ.The magnetic property,B_r of Bi/MnBi alloy decreases with the increase of R and increases with the increase of G_L.展开更多
We propose and demonstrate a dual-wavelength single-longitudinal-mode(SLM) fiber laser with switchable wavelength spacing based on a graphene saturable absorber(GSA) and a Wave Shaper. By virtue of the excellent satur...We propose and demonstrate a dual-wavelength single-longitudinal-mode(SLM) fiber laser with switchable wavelength spacing based on a graphene saturable absorber(GSA) and a Wave Shaper. By virtue of the excellent saturable absorption ability of graphene, the linewidths of the lasing wavelengths can be effectively reduced and eventually SLM operation can be obtained. The linewidths of both wavelengths are measured to be narrower than 7.3 kHz. The obtained results suggest that the graphene would be a good candidate nonlinear optical material for applications in related photonic fields, such as SLM oscillation generation for microwave generation and optical sensing.展开更多
Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial...Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.展开更多
We demonstrate the transmission of 2.5-Gb/s WDM signals spaced at 5 GHz over 480 km of single-mode fiber. The results indicate that it should be possible to transmit more than one thousand 2.5-Gb/s channels spaced at ...We demonstrate the transmission of 2.5-Gb/s WDM signals spaced at 5 GHz over 480 km of single-mode fiber. The results indicate that it should be possible to transmit more than one thousand 2.5-Gb/s channels spaced at 5 GHz over long distance.展开更多
It is proved that, for any elementary torsion free Fuchsian group F, the natural projection from the Teichmiiller curve V(F) to the Teichmiiller space T(F) has no holomorphic section.
文摘Eutectic Bi/MnBi magnetic alloy was prepared by directional solidification.When the growth rate,R>2 cm/h,the MnBi fibre spacing,λ,distributed homogeneously in Bi matrix,follows λ~2R=constant.The thermal gradient.G_L,does not influence λ.The magnetic property,B_r of Bi/MnBi alloy decreases with the increase of R and increases with the increase of G_L.
基金supported by the National Natural Science Foundation of China (No. 61475065)
文摘We propose and demonstrate a dual-wavelength single-longitudinal-mode(SLM) fiber laser with switchable wavelength spacing based on a graphene saturable absorber(GSA) and a Wave Shaper. By virtue of the excellent saturable absorption ability of graphene, the linewidths of the lasing wavelengths can be effectively reduced and eventually SLM operation can be obtained. The linewidths of both wavelengths are measured to be narrower than 7.3 kHz. The obtained results suggest that the graphene would be a good candidate nonlinear optical material for applications in related photonic fields, such as SLM oscillation generation for microwave generation and optical sensing.
文摘Erbium-doped holey fiber with hexagonal lattice was modeled by using effective index method. In order to calculate the equivalent step index of the periodic structure of the cladding holey optical fiber, all-vectorial fundamental space filling mode approach was utilized. By using EHll mode, we have numerically solved the rate equations of a three-level pumping scheme for a fiber laser. The obtained results have shown a good agreement with the other experimental results, recently. The results have predicted amplifiers with gain efficiencies as high as 10 dB/mW.
文摘We demonstrate the transmission of 2.5-Gb/s WDM signals spaced at 5 GHz over 480 km of single-mode fiber. The results indicate that it should be possible to transmit more than one thousand 2.5-Gb/s channels spaced at 5 GHz over long distance.
基金Supported by Program for New Century Excellent Talents in University (Grant No.NCET-06-0504)National Natural Science Foundation of China (Grant No.10771153)
文摘It is proved that, for any elementary torsion free Fuchsian group F, the natural projection from the Teichmiiller curve V(F) to the Teichmiiller space T(F) has no holomorphic section.