The characteristics of chirped and phase-shifted fiber Bragg gratings have been investigated by the use of transfer matrix formulation. While the characteristics of a chirped and phase-shifted fiber Bragg grating are ...The characteristics of chirped and phase-shifted fiber Bragg gratings have been investigated by the use of transfer matrix formulation. While the characteristics of a chirped and phase-shifted fiber Bragg grating are the same as those of non-chirped one in some important aspects, both the reflection and transmission windows of a chirped and phase-shifted fiber Bragg grating can be broadened in a wide range. Therefore, chirped and phase-shifted fiber Bragg gratings will have appScations in WDM or DWDM optical communication systems. The work in this paper can be used to design the new devices based on chirped and phase-shifted fiber Bragg gratings.展开更多
The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface p...The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface protection method and front surface passivation method have been used in the multicrystalline solar cells with ultra-small textured surfaces.With these improvements,the back surface remains intact after the etch process and the efficient minority lifetime is apparently increased.The test result shows that the solar cell with ultra-small textured surface can obtain better electrical performances by these improvements.展开更多
A solid-solution-phase Ba1.75Ca1.25MgSi2O8： Eu2＋, Mn2＋ phosphor in the photosynthetic action spectrum with dual band emissions at 438 nm and 660 nm is fabricated. X-ray diffraction （XRD） confirms the presence of ...A solid-solution-phase Ba1.75Ca1.25MgSi2O8： Eu2＋, Mn2＋ phosphor in the photosynthetic action spectrum with dual band emissions at 438 nm and 660 nm is fabricated. X-ray diffraction （XRD） confirms the presence of the solid-solution phase. With the supporting information from the diffuse reflection spectrum, a feasible way to obtain higher energy-transfer （ET） efficiency is attained, and the ET efficiency of Eu2＋-Mn2＋ is enhanced to 76%. The mechanism of this enhancement is owing to variation of the solid solution composition of Ca3MgSi208 and Ba3MgSi2Os, which contributes to the extension of the critical distance. Temperature-dependent results show an en- hancement which is attributed to Ca. These enhancements show great promise for improving coo-lighting devices.展开更多
文摘The characteristics of chirped and phase-shifted fiber Bragg gratings have been investigated by the use of transfer matrix formulation. While the characteristics of a chirped and phase-shifted fiber Bragg grating are the same as those of non-chirped one in some important aspects, both the reflection and transmission windows of a chirped and phase-shifted fiber Bragg grating can be broadened in a wide range. Therefore, chirped and phase-shifted fiber Bragg gratings will have appScations in WDM or DWDM optical communication systems. The work in this paper can be used to design the new devices based on chirped and phase-shifted fiber Bragg gratings.
基金supported by the National Basic Research Program of China("973" Project) (Grant No. 2009CB939703)the National Natural Science Foundation of China (Grant Nos. 11104319,51172268)the Chinese Academy of Solar Energy Action Plan and by Beijing Science and Technology Project (Grant No. Y2BK024001)
文摘The ultra-small textured surface of multicrystalline silicon solar cell,prepared by electroless chemical-etching method,shows an excellent anti-reflection property over a wide spectral bandwidth.A novel back surface protection method and front surface passivation method have been used in the multicrystalline solar cells with ultra-small textured surfaces.With these improvements,the back surface remains intact after the etch process and the efficient minority lifetime is apparently increased.The test result shows that the solar cell with ultra-small textured surface can obtain better electrical performances by these improvements.
基金supported by the National Natural Science Foundation of China(No.21076161)
文摘A solid-solution-phase Ba1.75Ca1.25MgSi2O8： Eu2＋, Mn2＋ phosphor in the photosynthetic action spectrum with dual band emissions at 438 nm and 660 nm is fabricated. X-ray diffraction （XRD） confirms the presence of the solid-solution phase. With the supporting information from the diffuse reflection spectrum, a feasible way to obtain higher energy-transfer （ET） efficiency is attained, and the ET efficiency of Eu2＋-Mn2＋ is enhanced to 76%. The mechanism of this enhancement is owing to variation of the solid solution composition of Ca3MgSi208 and Ba3MgSi2Os, which contributes to the extension of the critical distance. Temperature-dependent results show an en- hancement which is attributed to Ca. These enhancements show great promise for improving coo-lighting devices.
