A dynamical scheme is employed to simulate the self-trapping of the exciton in C_(60).During the self-trapping process,due to the bond distortion,two gap states A_(1u) and A_(2u) are separated from the highest occupie...A dynamical scheme is employed to simulate the self-trapping of the exciton in C_(60).During the self-trapping process,due to the bond distortion,two gap states A_(1u) and A_(2u) are separated from the highest occupied molecular orbital and the lowest unoccupied molecular orbital respectively.From the evolutions of the bond distortion and these two levels the relaxation time of the self-trapping exciton is about 90 fs.It is noticed that the relaxation of the exciton is much quicker than that of the charge transfer in C_(60).展开更多
Using infrared spectrum detective device, we experiment on Neiguan, Laogong and Hegu acupoints of seven adult volunteers as well as contrastive points beside ones. We get 63 infrared spectrums. The experiment outcome ...Using infrared spectrum detective device, we experiment on Neiguan, Laogong and Hegu acupoints of seven adult volunteers as well as contrastive points beside ones. We get 63 infrared spectrums. The experiment outcome tells us that the differences of the intensities among individuals are great, and so are the differences between acupoint and non-acupoint areas. However, the differences of spectral character are small, which indicates that infrared radiations of human body are based on the same biophysical fundament.展开更多
Magnetic ferroelectrics are one of the most important functional materials. The present bottleneck lim- iting applications of them is lacking of high-temperature single-phased ferromagnetic-ferroelectric multiferroics...Magnetic ferroelectrics are one of the most important functional materials. The present bottleneck lim- iting applications of them is lacking of high-temperature single-phased ferromagnetic-ferroelectric multiferroics with strong magnetoelectric coupling effect. Here, those progresses of the mechanism for coexistence of ferroelectric and magnetic order, experimental and theoretical studies on single-phased magnetic ferroelectrics, and the relationship between magnetic structure and crystal symmetry are summarized. With examples of BiFeO3, BiMnO3 and Bi2FeCrO6, the difficulties encountered in this field are analyzed. At last, some prospects to develop high-temperature single-phased ferromagnetic-ferro- electric multiferroics are also presented.展开更多
Molybdenum films were deposited on Corning 7059 glass substrates by DC magnetron sputtering with different working gas pressures and sputtering powers.The structure and morphology,residual stress and adhesion,resistiv...Molybdenum films were deposited on Corning 7059 glass substrates by DC magnetron sputtering with different working gas pressures and sputtering powers.The structure and morphology,residual stress and adhesion,resistivity and optical reflectance of the as-deposited Mo films were investigated.The results show that Mo films deposited with high working gas pressure and low sputtering power have a spherical surface morphology,small grain size,residual compressive stress and a good adhesion,high resistivity and low optical reflectance.With the working gas pressure decreased and the sputtering power increased,Mo films have elongated spindle-shape or diamond flake shape surface morphology,the grain size is increased,with residual stress changed from tensile to compressive,a poor adhesion,resistivity decreased and optical reflectance increased.展开更多
Manipulation of spin states via purely electric means forms the research branch "all-electric spintronics".In this paper,we briefly review recent progress relating to the all-electric spintronics,including e...Manipulation of spin states via purely electric means forms the research branch "all-electric spintronics".In this paper,we briefly review recent progress relating to the all-electric spintronics,including electric-field control of Rashba spin-orbit coupling,magnetic anisotropy,exchange bias,ferromagnetism,and other forms of magnetoelectric coupling.Special focus is given to surface/interface systems,including semiconductor(oxide) heterostructures,magnetic/nonmagnetic surfaces,semiconductor-metal interfaces,and other nanostructures,which can be good candidates for functional materials for spintronic.展开更多
As relaxor ferroelectric functional materials, their crystal structures depend on temperature, component, electric filed, pressure, and so on, which are important for the applications of sensors, transducers, and actu...As relaxor ferroelectric functional materials, their crystal structures depend on temperature, component, electric filed, pressure, and so on, which are important for the applications of sensors, transducers, and actuators. For the case of Pb Ti O_3-based ferroelectrics Pb(Zn_(1/3)Nb_(2/3))O_3-Pb Ti O_3, Pb(Mg_(1/3)Nb_(2/3))O_3-Pb Ti O_3, Pb(In_(1/2)Nb_(1/2))O_3-Pb(Mg_(1/3)Nb_(2/3))O_3-Pb Ti O_3 and some other crystals, they have been extensively investigated due to the excellent electromechanical and piezoelectric properties. Generally, ferroelectric crystal structure and corresponding phase diagram are detected by temperature-dependent high resolution X-ray diffraction, low frequency dielectric permittivity, and domain structures. In this review, we focus on the novel condensed matter spectroscopy(i.e., spectroscopic ellipsometry, transmittance, photoluminescence spectra as well as Raman spectra), which is nondestructive, noncontact, and sensitive optical techniques for probing symmetries, phase transitions and phase diagrams of ferroelectric crystals. Besides, it can supply some other physical and chemical information for ferroelectric and semiconductor functional materials such as optical band gap, electronic transitions, dielectric functions, optical conductivity, absorption, phonon modes, lattice dynamics as functions of temperature and PT composition.展开更多
基金Supported by the National Natural Science Foundation of ChinaAdvanced Material Committee of China,rmd KOSEF 94080011013.
文摘A dynamical scheme is employed to simulate the self-trapping of the exciton in C_(60).During the self-trapping process,due to the bond distortion,two gap states A_(1u) and A_(2u) are separated from the highest occupied molecular orbital and the lowest unoccupied molecular orbital respectively.From the evolutions of the bond distortion and these two levels the relaxation time of the self-trapping exciton is about 90 fs.It is noticed that the relaxation of the exciton is much quicker than that of the charge transfer in C_(60).
基金the Climbing Project(Grant No. 95-19-311), the National Natural Science Foundation of China (Grant Nos. 39800188 and 39870947), the Science and Technology Development Foundation of Shanghai (Grant Nos. 99JC14048, 99ZB14043 and 994119075), the Visiting
文摘Using infrared spectrum detective device, we experiment on Neiguan, Laogong and Hegu acupoints of seven adult volunteers as well as contrastive points beside ones. We get 63 infrared spectrums. The experiment outcome tells us that the differences of the intensities among individuals are great, and so are the differences between acupoint and non-acupoint areas. However, the differences of spectral character are small, which indicates that infrared radiations of human body are based on the same biophysical fundament.
基金supported by the National Natural Science Foundation of China (Grant No. 10304021)National Basic Research Program of China (Grant No. 2007CB924900)+2 种基金Foundation for the Author of National Excellent Doctoral Dissertation of China (FANEDD-200744)Shanghai Pujiang Program (Grant No. 07pj14087)Program for New Century Excellent Talents in University (NCET-07-0624)
文摘Magnetic ferroelectrics are one of the most important functional materials. The present bottleneck lim- iting applications of them is lacking of high-temperature single-phased ferromagnetic-ferroelectric multiferroics with strong magnetoelectric coupling effect. Here, those progresses of the mechanism for coexistence of ferroelectric and magnetic order, experimental and theoretical studies on single-phased magnetic ferroelectrics, and the relationship between magnetic structure and crystal symmetry are summarized. With examples of BiFeO3, BiMnO3 and Bi2FeCrO6, the difficulties encountered in this field are analyzed. At last, some prospects to develop high-temperature single-phased ferromagnetic-ferro- electric multiferroics are also presented.
基金supported by the knowledge innovation program of the Chinese academy of sciences(Grant No.KGCX2-YW-347)
文摘Molybdenum films were deposited on Corning 7059 glass substrates by DC magnetron sputtering with different working gas pressures and sputtering powers.The structure and morphology,residual stress and adhesion,resistivity and optical reflectance of the as-deposited Mo films were investigated.The results show that Mo films deposited with high working gas pressure and low sputtering power have a spherical surface morphology,small grain size,residual compressive stress and a good adhesion,high resistivity and low optical reflectance.With the working gas pressure decreased and the sputtering power increased,Mo films have elongated spindle-shape or diamond flake shape surface morphology,the grain size is increased,with residual stress changed from tensile to compressive,a poor adhesion,resistivity decreased and optical reflectance increased.
基金supported by the National Basic Research Program of China(Grant No.2013CB922300)the National Natural Science Foundation of China(Grant Nos.11004211,61125403 and 50832003)+1 种基金PCSIRT, NCET,ECNU Fostering Project for Top Doctoral DissertationsFundamental Research Funds for the central universities(ECNU)
文摘Manipulation of spin states via purely electric means forms the research branch "all-electric spintronics".In this paper,we briefly review recent progress relating to the all-electric spintronics,including electric-field control of Rashba spin-orbit coupling,magnetic anisotropy,exchange bias,ferromagnetism,and other forms of magnetoelectric coupling.Special focus is given to surface/interface systems,including semiconductor(oxide) heterostructures,magnetic/nonmagnetic surfaces,semiconductor-metal interfaces,and other nanostructures,which can be good candidates for functional materials for spintronic.
基金supported by the Major State Basic Research Development Program of China(Grant No.2013CB922300&2011CB922200)the National Natural Science Foundation of China(Grant Nos.11374097,61376129&61504156)+1 种基金the Projects of Science and Technology Commission of Shanghai Municipality(Grant Nos.15JC1401600,14XD1401500,13JC1402100&13JC1404200)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning
文摘As relaxor ferroelectric functional materials, their crystal structures depend on temperature, component, electric filed, pressure, and so on, which are important for the applications of sensors, transducers, and actuators. For the case of Pb Ti O_3-based ferroelectrics Pb(Zn_(1/3)Nb_(2/3))O_3-Pb Ti O_3, Pb(Mg_(1/3)Nb_(2/3))O_3-Pb Ti O_3, Pb(In_(1/2)Nb_(1/2))O_3-Pb(Mg_(1/3)Nb_(2/3))O_3-Pb Ti O_3 and some other crystals, they have been extensively investigated due to the excellent electromechanical and piezoelectric properties. Generally, ferroelectric crystal structure and corresponding phase diagram are detected by temperature-dependent high resolution X-ray diffraction, low frequency dielectric permittivity, and domain structures. In this review, we focus on the novel condensed matter spectroscopy(i.e., spectroscopic ellipsometry, transmittance, photoluminescence spectra as well as Raman spectra), which is nondestructive, noncontact, and sensitive optical techniques for probing symmetries, phase transitions and phase diagrams of ferroelectric crystals. Besides, it can supply some other physical and chemical information for ferroelectric and semiconductor functional materials such as optical band gap, electronic transitions, dielectric functions, optical conductivity, absorption, phonon modes, lattice dynamics as functions of temperature and PT composition.
