By applying the perturbation method and the complex-source-point theory, the theoretical research of measurement of complex permittivity of uniaxial anisotropic materials by means of an electromagnetic open resonator ...By applying the perturbation method and the complex-source-point theory, the theoretical research of measurement of complex permittivity of uniaxial anisotropic materials by means of an electromagnetic open resonator has been made, and the double refraction phenomenon due to anisotropy of measured dielectric materials has been quantitatively analyzed. Finally, measurements have been made on some single-crystal quartz specimens using an automated open resonator measurement system at 8mm band.展开更多
In microwave engineering and the application of microwave energy, computation of the Q-factor of a microwave resonator is very important. This work will be very difficult when the geometric structure or the field dist...In microwave engineering and the application of microwave energy, computation of the Q-factor of a microwave resonator is very important. This work will be very difficult when the geometric structure or the field distribution of the resonator is complicated. Therefore, attentions have been paid to searching simple and useful methods for the problem. In 1984, D. Kajfez presented the incremental frequency rule展开更多
Optical nanoantennas can convert propagating light to local fields.The local-field responses can be engineered to exhibit nontrivial features in spatial,spectral and temporal domains,where local-field interferences pl...Optical nanoantennas can convert propagating light to local fields.The local-field responses can be engineered to exhibit nontrivial features in spatial,spectral and temporal domains,where local-field interferences play a key role.Here,we design nearly fully controllable local-field interferences in the nanogap of a nanoantenna,and experimentally demonstrate that in the nanogap,the spectral dispersion of the local-field response can exhibit tuneable Fano lineshapes with nearly vanishing Fano dips.A single quantum dot is precisely positioned in the nanogap to probe the spectral dispersions of the local-field responses.By controlling the excitation polarization,the asymmetry parameter q of the probed Fano lineshapes can be tuned from negative to positive values,and correspondingly,the Fano dips can be tuned across a broad spectral range.Notably,at the Fano dips,the local-field intensity is strongly suppressed by up to ~50-fold,implying that the hot spot in the nanogap can be turned into a cold spot.The results may inspire diverse designs of local-field responses with novel spatial distributions,spectral dispersions and temporal dynamics,and expand the available toolbox for nanoscopy,spectroscopy,nano-optical quantum control and nanolithography.展开更多
We report the application of multilayered polyelectrolyte-coated gold nanorods(GNRs) as multifunctional optical contrast agents for cancer cell imaging.The surface modification of GNRs improves their chemical stabilit...We report the application of multilayered polyelectrolyte-coated gold nanorods(GNRs) as multifunctional optical contrast agents for cancer cell imaging.The surface modification of GNRs improves their chemical stability and facilitates them to be taken up by cancer cells through electrostatic interaction.The unique longitudinal surface plasmon resonance property of GNRs makes them suitable as both "scattering contrast agents" and "Raman contrast agents".In our experiments,the staining of GNRs in cells was further confirmed by dark field microscopy and Raman microscopy.Our experiment results indicated that GNRs have great potential as multifunctional "optical contrast agents" for future in vivo animal imaging.展开更多
Though the concept of mutual capcitance has been given in circuit theory, it is hard to realize mutual capacitance compared with mutual inductance. Ref.[2] deals with the coupling of two capacitors consisting of four ...Though the concept of mutual capcitance has been given in circuit theory, it is hard to realize mutual capacitance compared with mutual inductance. Ref.[2] deals with the coupling of two capacitors consisting of four conductors. This note deals with the coupling of N capacitance loops consisting of 2N conductors. From it is deduced a relation among the mutual capacitance matrix of the loop capcitance coefficient matrix and the partial capcitance matrix of the conductor system.展开更多
基金Supported by the Doctoral Fbundation of the State Education Commission of China
文摘By applying the perturbation method and the complex-source-point theory, the theoretical research of measurement of complex permittivity of uniaxial anisotropic materials by means of an electromagnetic open resonator has been made, and the double refraction phenomenon due to anisotropy of measured dielectric materials has been quantitatively analyzed. Finally, measurements have been made on some single-crystal quartz specimens using an automated open resonator measurement system at 8mm band.
文摘In microwave engineering and the application of microwave energy, computation of the Q-factor of a microwave resonator is very important. This work will be very difficult when the geometric structure or the field distribution of the resonator is complicated. Therefore, attentions have been paid to searching simple and useful methods for the problem. In 1984, D. Kajfez presented the incremental frequency rule
基金supported by the National Key Research and Development Program of China(2017YFA0205700)the National Natural Science Foundation of China(11621101,61774131,91833303)+2 种基金the Fundamental Research Funds for the Central Universities(2017FZA5001,2018FZA5001)the China Postdoctoral Science Foundation(2017M621920,2017M622722)the Science and Technology Department of Zhejiang Province and the Guangdong Innovative Research Team Program(201001D0104799318).
文摘Optical nanoantennas can convert propagating light to local fields.The local-field responses can be engineered to exhibit nontrivial features in spatial,spectral and temporal domains,where local-field interferences play a key role.Here,we design nearly fully controllable local-field interferences in the nanogap of a nanoantenna,and experimentally demonstrate that in the nanogap,the spectral dispersion of the local-field response can exhibit tuneable Fano lineshapes with nearly vanishing Fano dips.A single quantum dot is precisely positioned in the nanogap to probe the spectral dispersions of the local-field responses.By controlling the excitation polarization,the asymmetry parameter q of the probed Fano lineshapes can be tuned from negative to positive values,and correspondingly,the Fano dips can be tuned across a broad spectral range.Notably,at the Fano dips,the local-field intensity is strongly suppressed by up to ~50-fold,implying that the hot spot in the nanogap can be turned into a cold spot.The results may inspire diverse designs of local-field responses with novel spatial distributions,spectral dispersions and temporal dynamics,and expand the available toolbox for nanoscopy,spectroscopy,nano-optical quantum control and nanolithography.
基金supported by the Swedish Foundation for Strategic Research (SSF) and the US Air Force Office of Scientific Research (Asia Office)
文摘We report the application of multilayered polyelectrolyte-coated gold nanorods(GNRs) as multifunctional optical contrast agents for cancer cell imaging.The surface modification of GNRs improves their chemical stability and facilitates them to be taken up by cancer cells through electrostatic interaction.The unique longitudinal surface plasmon resonance property of GNRs makes them suitable as both "scattering contrast agents" and "Raman contrast agents".In our experiments,the staining of GNRs in cells was further confirmed by dark field microscopy and Raman microscopy.Our experiment results indicated that GNRs have great potential as multifunctional "optical contrast agents" for future in vivo animal imaging.
文摘Though the concept of mutual capcitance has been given in circuit theory, it is hard to realize mutual capacitance compared with mutual inductance. Ref.[2] deals with the coupling of two capacitors consisting of four conductors. This note deals with the coupling of N capacitance loops consisting of 2N conductors. From it is deduced a relation among the mutual capacitance matrix of the loop capcitance coefficient matrix and the partial capcitance matrix of the conductor system.
