以N-(3-二甲氨基丙基)甲基丙烯酰胺(DMAPMA)和丙烯酰胺(AM)为单体,以过硫酸铵和亚硫酸氢钠为引发剂进行自由基聚合,合成了一种CO_2/N_2开关响应型聚合物P(DMAPMA-AM)。通过单因素实验得出最佳合成条件为:n(AM)∶n(DMAPMA)=4∶1、单体总...以N-(3-二甲氨基丙基)甲基丙烯酰胺(DMAPMA)和丙烯酰胺(AM)为单体,以过硫酸铵和亚硫酸氢钠为引发剂进行自由基聚合,合成了一种CO_2/N_2开关响应型聚合物P(DMAPMA-AM)。通过单因素实验得出最佳合成条件为:n(AM)∶n(DMAPMA)=4∶1、单体总质量分数为25%、n[(NH_4)_2S_2O_8]∶n(NaHSO_3)=2∶3、引发剂加入量为单体总质量的0.2%、反应温度40℃、反应时间4 h。用FTIR、1HNMR对产物进行了结构表征,测量了质量分数为0.2%的聚合物水溶液在通入CO_2/N2前后的电导率、Zeta电位和平均粒径,并对其乳化性能进行了考察。结果表明:在通入CO_2后,溶液的电导率由12.6μs/cm上升到40.7μs/cm,Zeta电位由1.25 m V上升到10.11 m V,平均粒径由708.6 nm降低到137.1 nm,而向溶液改通N2后溶液的电导率降到14.2μs/cm,Zeta电位下降到1.96 m V,平均粒径上升到589.8 nm,表明P(DMAPMA-AM)具有可逆的CO_2/N2开关响应性能。扫描电镜测试发现,通入CO_2/N_2前后聚合物线团的尺寸以及疏水颗粒的数目发生了显著变化。CO_2/N2能将聚合产物存在的油水混合体系进行有效的破乳/乳化。展开更多
We report the observation of asymmetric switching dual peaks in ferroelectric copolymer films. These dual peaks occurs when the poling electric field is just below the coercive field and can be removed by continuous a...We report the observation of asymmetric switching dual peaks in ferroelectric copolymer films. These dual peaks occurs when the poling electric field is just below the coercive field and can be removed by continuous application of high enough switching voltage. Our experimental observations can be explained by the injection and the redistribution of space charges in ferroelectric films.展开更多
By using poled-polymer/silicon slot waveguides in the active region and the Pockels effect of the poled-polymer,we propose a kind of Mach-Zehnder interferometer(MZI) electro-optic(EO) switch operated at 1 550 nm.Struc...By using poled-polymer/silicon slot waveguides in the active region and the Pockels effect of the poled-polymer,we propose a kind of Mach-Zehnder interferometer(MZI) electro-optic(EO) switch operated at 1 550 nm.Structural parameters are optimized for realizing normal switching function.Dependencies of switching characteristics on the slot waveguide parameters are investigated.For the silicon strip with dimension of 170 nm×300 nm,as the slot width varies from 50 nm to 100 nm,the switching voltage can be as low as 1.0 V with active region length of only 0.17–0.35 mm,and the length of the whole device is only about 770–950 μm.The voltage-length product of this switching structure is only 0.17–0.35 V·mm,and it is at least 19–40 times smaller than that of the traditional polymer MZI EO switch,which is 6.69 V·mm.Compared with our previously reported MZI EO switches,this switch exhibits some superior characteristics,including low switching voltage,compact device size and small wavelength dependency.展开更多
Structure and design are proposed for a kind of novel polymer Mach-Zehnder electro-optic(EO)switch using side-coupled M series-cascaded EO microrings.Formulations are proposed to analyze its switching characteristics....Structure and design are proposed for a kind of novel polymer Mach-Zehnder electro-optic(EO)switch using side-coupled M series-cascaded EO microrings.Formulations are proposed to analyze its switching characteristics.The dependences of the device’s performances on M are thoroughly analyzed and concluded.As the increase of M from 2 to 10,the switching voltages for the 9 devices are as low as 0.84 V,0.82 V,0.52 V,0.5 V,0.37 V,0.36 V,0.29 V,0.28 V and 0.24 V,respectively;whereas the crosstalks under bar state are within-20.79--6.53 d B and those under cross state are within-20.36--5.29 d B.The analysis results indicate that a smaller M is preferred for dropping the insertion loss and crosstalk,and a larger M should be selected to increase the optical bandwidth and minimize the switching energy.Generally,due to low switching voltage,the proposed device shows potential applications in optical networks-on-chip.展开更多
文摘以N-(3-二甲氨基丙基)甲基丙烯酰胺(DMAPMA)和丙烯酰胺(AM)为单体,以过硫酸铵和亚硫酸氢钠为引发剂进行自由基聚合,合成了一种CO_2/N_2开关响应型聚合物P(DMAPMA-AM)。通过单因素实验得出最佳合成条件为:n(AM)∶n(DMAPMA)=4∶1、单体总质量分数为25%、n[(NH_4)_2S_2O_8]∶n(NaHSO_3)=2∶3、引发剂加入量为单体总质量的0.2%、反应温度40℃、反应时间4 h。用FTIR、1HNMR对产物进行了结构表征,测量了质量分数为0.2%的聚合物水溶液在通入CO_2/N2前后的电导率、Zeta电位和平均粒径,并对其乳化性能进行了考察。结果表明:在通入CO_2后,溶液的电导率由12.6μs/cm上升到40.7μs/cm,Zeta电位由1.25 m V上升到10.11 m V,平均粒径由708.6 nm降低到137.1 nm,而向溶液改通N2后溶液的电导率降到14.2μs/cm,Zeta电位下降到1.96 m V,平均粒径上升到589.8 nm,表明P(DMAPMA-AM)具有可逆的CO_2/N2开关响应性能。扫描电镜测试发现,通入CO_2/N_2前后聚合物线团的尺寸以及疏水颗粒的数目发生了显著变化。CO_2/N2能将聚合产物存在的油水混合体系进行有效的破乳/乳化。
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.10804020）, the Specialized Research Fund for the Doctoral Program of Higher Education of China （No.200802461088）, and the Shanghai Leading Academic Discipline Project （No.B113）.
文摘We report the observation of asymmetric switching dual peaks in ferroelectric copolymer films. These dual peaks occurs when the poling electric field is just below the coercive field and can be removed by continuous application of high enough switching voltage. Our experimental observations can be explained by the injection and the redistribution of space charges in ferroelectric films.
基金supported by the National Natural Science Foundation of China(Nos.61107021,61177027 and 61077074)the Ministry of Education of China(Nos.20110061120052 and 20120061130008)the Science and Technology Department of Jilin Province of China(No.20130522161JH)
文摘By using poled-polymer/silicon slot waveguides in the active region and the Pockels effect of the poled-polymer,we propose a kind of Mach-Zehnder interferometer(MZI) electro-optic(EO) switch operated at 1 550 nm.Structural parameters are optimized for realizing normal switching function.Dependencies of switching characteristics on the slot waveguide parameters are investigated.For the silicon strip with dimension of 170 nm×300 nm,as the slot width varies from 50 nm to 100 nm,the switching voltage can be as low as 1.0 V with active region length of only 0.17–0.35 mm,and the length of the whole device is only about 770–950 μm.The voltage-length product of this switching structure is only 0.17–0.35 V·mm,and it is at least 19–40 times smaller than that of the traditional polymer MZI EO switch,which is 6.69 V·mm.Compared with our previously reported MZI EO switches,this switch exhibits some superior characteristics,including low switching voltage,compact device size and small wavelength dependency.
基金supported by the National Natural Science Foundation of China(Nos.61107021,61177027 and 61077074)the Ministry of Education of China(Nos.20110061120052 and 20120061130008)the Science and Technology Department of Jilin Province of China(No.20130522161JH)
文摘Structure and design are proposed for a kind of novel polymer Mach-Zehnder electro-optic(EO)switch using side-coupled M series-cascaded EO microrings.Formulations are proposed to analyze its switching characteristics.The dependences of the device’s performances on M are thoroughly analyzed and concluded.As the increase of M from 2 to 10,the switching voltages for the 9 devices are as low as 0.84 V,0.82 V,0.52 V,0.5 V,0.37 V,0.36 V,0.29 V,0.28 V and 0.24 V,respectively;whereas the crosstalks under bar state are within-20.79--6.53 d B and those under cross state are within-20.36--5.29 d B.The analysis results indicate that a smaller M is preferred for dropping the insertion loss and crosstalk,and a larger M should be selected to increase the optical bandwidth and minimize the switching energy.Generally,due to low switching voltage,the proposed device shows potential applications in optical networks-on-chip.
