中国1.8 m太阳望远镜(Chinese large solar telescope,CLST)致力于对太阳偏振的高精度及高灵敏度测量。然而其系统本身会引入仪器偏振,并且在望远镜运行的过程中,仪器偏振会随其指向的变化而变化。这就降低了系统的测量精度。因此,需要...中国1.8 m太阳望远镜(Chinese large solar telescope,CLST)致力于对太阳偏振的高精度及高灵敏度测量。然而其系统本身会引入仪器偏振,并且在望远镜运行的过程中,仪器偏振会随其指向的变化而变化。这就降低了系统的测量精度。因此,需要一个偏振标定单元对其仪器偏振进行标定。为此,本文对偏振标定的原理和方法进行了研究,并且给出了针对CLST的偏振标定单元设计方案。展开更多
Using a lithium niobate （LN） material, we propose a broadband polarization beam splitter （PBS） with high efficiency by employing a negative refractive photonic crystal （PhC） wedge slab with an angle of 60°....Using a lithium niobate （LN） material, we propose a broadband polarization beam splitter （PBS） with high efficiency by employing a negative refractive photonic crystal （PhC） wedge slab with an angle of 60°. It can split the incident light into two parts at about 90° with TE and TM polarizations. The transmissions of polarized light for an LN-based PBS are more than 80% with a broad angle and wavelength bandwidth of 8° and 70 nm at 1.55μm, while with a Si-based PhC, no PBS with high efficiency can be realized for the relatively lower transmission of TM output light.展开更多
A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a ...A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a high energy load.The relationship between reflectivity and input energy is examined experimentally with different PCM structures,focus lengths,and medium cell structures.A medium cell with a circulating structure is designed,and its advantage is demonstrated through an experimental comparison with traditional PCM structures.The 30-cm focus lens and 150-cm collimation lens are optimized when the input energy reaches 1010 mJ at 10-Hz repetition rate.Therefore,a reflectivity of 84.7% and a higher energy load using the circulating two-cell structure are achieved.展开更多
The reflection and transmittance of s- and p-polarized lights should be treated separately at nonzero angle incidence. By choosing two special film materials whose refractive indices meet the Brewster condition in a g...The reflection and transmittance of s- and p-polarized lights should be treated separately at nonzero angle incidence. By choosing two special film materials whose refractive indices meet the Brewster condition in a given incident angle, the reflection of p-polarized light can be eliminated. When the two materials are fabricated into multilayer stacks, the reflection of s-polarized light can be largely increased while the reflection of p-polarized light keeps low. According to this principle, a film polarizer with bandwidth of 198 nm or even more is designed.展开更多
We propose a wideband transverse magnetic-reflected polarizing film composed of Cr and SiO2. Based on the polarization characteristics of reflected light from Cr/SiO2 film, the film can serves as a polarizer to severe...We propose a wideband transverse magnetic-reflected polarizing film composed of Cr and SiO2. Based on the polarization characteristics of reflected light from Cr/SiO2 film, the film can serves as a polarizer to severely attenuate the transverse electric （TE）-polarized light and reflect the transverse magnetic （TM）- polarized light in a wavelength range from 600 to 900 nm. By suitably choosing the film thicknesses, the operation angles of such polarizers can be adjusted over a wide angle range greater than the critical angle of total reflection. Cr/SiO2 film has potential use in surface plasmon resonance （SPR） sensors based on Kretchmann configuration to form integrated structures.展开更多
A dual-core photonic crystal fiber(PCF)polarization splitter based on lead silicate glass is proposed.The characteristics of the polarization splitter are analyzed using full-vector finite element method.Compared with...A dual-core photonic crystal fiber(PCF)polarization splitter based on lead silicate glass is proposed.The characteristics of the polarization splitter are analyzed using full-vector finite element method.Compared with the silica glass PCF polarization splitter with the same structure,it is shown that the new material polarizer can realize splitting with less coupling loss and higher extinction ratio.When the wavelength is 1 550 nm and the PCF length in the beam splitter is 688μm,the coupling loss is only 0.001 9 d B,and the extinction ratio for the input core is-64.1 d B.展开更多
文摘中国1.8 m太阳望远镜(Chinese large solar telescope,CLST)致力于对太阳偏振的高精度及高灵敏度测量。然而其系统本身会引入仪器偏振,并且在望远镜运行的过程中,仪器偏振会随其指向的变化而变化。这就降低了系统的测量精度。因此,需要一个偏振标定单元对其仪器偏振进行标定。为此,本文对偏振标定的原理和方法进行了研究,并且给出了针对CLST的偏振标定单元设计方案。
基金supported by the National Natural Science Foundation of China under Grant Nos.11574208 and 1174204
文摘Using a lithium niobate （LN） material, we propose a broadband polarization beam splitter （PBS） with high efficiency by employing a negative refractive photonic crystal （PhC） wedge slab with an angle of 60°. It can split the incident light into two parts at about 90° with TE and TM polarizations. The transmissions of polarized light for an LN-based PBS are more than 80% with a broad angle and wavelength bandwidth of 8° and 70 nm at 1.55μm, while with a Si-based PhC, no PBS with high efficiency can be realized for the relatively lower transmission of TM output light.
基金supported by the National Natural Science Foundation of China(No. 60878005)the China Postdoctoral Science Foundation(No. 20090450966)+1 种基金the Heilongjiang Postdoctoral Science Foundationthe Natural Scientific Research Innovation Foundation in Harbin Institute of Technology(No. HIT. NSRIF.2009010)
文摘A new approach to realize high-energy and high-power stimulated Brillouin scattering phase conjugation mirrors （SBS-PCMs） is described.The reflectivity of SBS-PCM is investigated under a 10-Hz repetition rate and a high energy load.The relationship between reflectivity and input energy is examined experimentally with different PCM structures,focus lengths,and medium cell structures.A medium cell with a circulating structure is designed,and its advantage is demonstrated through an experimental comparison with traditional PCM structures.The 30-cm focus lens and 150-cm collimation lens are optimized when the input energy reaches 1010 mJ at 10-Hz repetition rate.Therefore,a reflectivity of 84.7% and a higher energy load using the circulating two-cell structure are achieved.
文摘The reflection and transmittance of s- and p-polarized lights should be treated separately at nonzero angle incidence. By choosing two special film materials whose refractive indices meet the Brewster condition in a given incident angle, the reflection of p-polarized light can be eliminated. When the two materials are fabricated into multilayer stacks, the reflection of s-polarized light can be largely increased while the reflection of p-polarized light keeps low. According to this principle, a film polarizer with bandwidth of 198 nm or even more is designed.
基金supported by the National Natural Science Foundation of China(No.61177079)the Young Scientists Fund of the National Natural Science Foundation of China(No.61205071.)
文摘We propose a wideband transverse magnetic-reflected polarizing film composed of Cr and SiO2. Based on the polarization characteristics of reflected light from Cr/SiO2 film, the film can serves as a polarizer to severely attenuate the transverse electric （TE）-polarized light and reflect the transverse magnetic （TM）- polarized light in a wavelength range from 600 to 900 nm. By suitably choosing the film thicknesses, the operation angles of such polarizers can be adjusted over a wide angle range greater than the critical angle of total reflection. Cr/SiO2 film has potential use in surface plasmon resonance （SPR） sensors based on Kretchmann configuration to form integrated structures.
基金supported by the National Natural Science Foundation of China(No.11004152)
文摘A dual-core photonic crystal fiber(PCF)polarization splitter based on lead silicate glass is proposed.The characteristics of the polarization splitter are analyzed using full-vector finite element method.Compared with the silica glass PCF polarization splitter with the same structure,it is shown that the new material polarizer can realize splitting with less coupling loss and higher extinction ratio.When the wavelength is 1 550 nm and the PCF length in the beam splitter is 688μm,the coupling loss is only 0.001 9 d B,and the extinction ratio for the input core is-64.1 d B.
