Effects of crystal structures on dielectric properties of ATiO_(3)(trigonal ilmenite),ATa_(2)O_(6)(tetragonal tri-rutile)and AWO_(4)(monoclinic wolframite)(A=Ni,Mg,Co)ceramics with A-and B-site oxygen octahedra were i...Effects of crystal structures on dielectric properties of ATiO_(3)(trigonal ilmenite),ATa_(2)O_(6)(tetragonal tri-rutile)and AWO_(4)(monoclinic wolframite)(A=Ni,Mg,Co)ceramics with A-and B-site oxygen octahedra were investigated at microwave frequencies.The dielectric constant(K) of the specimens was affected by the dielectric polarizabilities of composition and cation bond valence between octahedral cation and oxygen ion per molar volum(V_(m)).The quality factor(Qf)of ATiO_(3)was appreciably larger than those of ATa_(2)O_(6)and AWO_(4)due to the different sharing types of oxygen octahedra.The temperature coe±cient of resonant frequency(TCF)of the specimens was dependent on the octahedral distortion per V_(m).展开更多
Plasmonic effects that enhance electric fields and amplify optical signals are crucial for improving the resolution of optical imaging systems. In this paper, a metal-based plasmonic nanostructure (MPN) is designed to...Plasmonic effects that enhance electric fields and amplify optical signals are crucial for improving the resolution of optical imaging systems. In this paper, a metal-based plasmonic nanostructure (MPN) is designed to increase the resolution of an optical imaging system by amplifying a specific signal while producing a plasmonic effect via a dipole nanoantenna (DN) and grating nanostructure (GN), which couple the electric field to be focused at the center of the unit cell. We confirmed that the MPN enhances electric fields 15 times more than the DN and GN, enabling the acquisition of finely resolved optical signals. The experiments confirmed that compared with the initial laser intensity, the MPN, which was fabricated by nanoimprint lithography, enhanced the optical signal of the laser by 2.24 times. Moreover, when the MPN was applied in two optical imaging systems, an indistinguishable signal that was similar to noise in original was distinguished by amplifying the optical signal as 106 times in functional near-infrared spectroscopy(fNIRS), and a specific wavelength was enhanced in fluorescence image. Thus, the incorporation of this nanostructure increased the utility of the collected data and could enhance optical signals in optics, bioimaging, and biology applications.展开更多
基金This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(2009-0078000).
文摘Effects of crystal structures on dielectric properties of ATiO_(3)(trigonal ilmenite),ATa_(2)O_(6)(tetragonal tri-rutile)and AWO_(4)(monoclinic wolframite)(A=Ni,Mg,Co)ceramics with A-and B-site oxygen octahedra were investigated at microwave frequencies.The dielectric constant(K) of the specimens was affected by the dielectric polarizabilities of composition and cation bond valence between octahedral cation and oxygen ion per molar volum(V_(m)).The quality factor(Qf)of ATiO_(3)was appreciably larger than those of ATa_(2)O_(6)and AWO_(4)due to the different sharing types of oxygen octahedra.The temperature coe±cient of resonant frequency(TCF)of the specimens was dependent on the octahedral distortion per V_(m).
基金National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.2022R1A2B5B01002377)Following are results of a study on the“Leaders in Industry-university Cooperation 3.0”Project,supported by the Ministry of Education and National Research Foundation of Korea.
文摘Plasmonic effects that enhance electric fields and amplify optical signals are crucial for improving the resolution of optical imaging systems. In this paper, a metal-based plasmonic nanostructure (MPN) is designed to increase the resolution of an optical imaging system by amplifying a specific signal while producing a plasmonic effect via a dipole nanoantenna (DN) and grating nanostructure (GN), which couple the electric field to be focused at the center of the unit cell. We confirmed that the MPN enhances electric fields 15 times more than the DN and GN, enabling the acquisition of finely resolved optical signals. The experiments confirmed that compared with the initial laser intensity, the MPN, which was fabricated by nanoimprint lithography, enhanced the optical signal of the laser by 2.24 times. Moreover, when the MPN was applied in two optical imaging systems, an indistinguishable signal that was similar to noise in original was distinguished by amplifying the optical signal as 106 times in functional near-infrared spectroscopy(fNIRS), and a specific wavelength was enhanced in fluorescence image. Thus, the incorporation of this nanostructure increased the utility of the collected data and could enhance optical signals in optics, bioimaging, and biology applications.
