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81.
A Josephson current through a half-metallic ferromagnet between two conventional superconductors is theoretically studied. The spin dynamics such as magnon excitation plays a crucial role not only for the conversion between spin-singlet and spin-triplet pairs but also for the formation of the composite state of a triplet Cooper pair and magnon, by which the Josephson current flows between the superconductors. We propose the supercurrent pumping driven by the coherent precession of the magnetization by tuning the microwave frequency to the ferromagnetic resonance frequency in a ferromagnetic Josephson junction. 相似文献
82.
83.
Susumu Takahashi Dan G. Allen Jason Seifter Gerald Ramian Mark S. Sherwin Louis-Claude Brunel Johan van Tol 《Infrared Physics & Technology》2008,51(5):426-428
We describe the first free-electron laser (FEL)-based pulsed electron paramagnetic resonance (EPR) system designed to study spin dynamics and structure changes of proteins in aqueous solution with nano-second of time resolution. This novel approach opens up the possibility for high-power sub-THz and THz pulsed EPR spectroscopy. 相似文献
84.
T.M. Nakatani Y.K. Takahashi M. Yamamoto 《Journal of magnetism and magnetic materials》2010,322(3):357-361
We have investigated the structure of Co2MnSi/MgO/Co2MnSi magnetic tunneling junctions with different tunnel magnetoresistance values depending on the in situ annealing temperatures just after the deposition of the upper Co2MnSi electrodes. The nano-beam diffraction patterns indicated that the degree of order of the upper Co2MnSi electrode annealed at 550 °C was higher than that of an electrode annealed at 400 °C. Moreover, the degree of the L21 order of the upper Co2MnSi electrode annealed at 550 °C was even lower than that of the lower Co2MnSi electrode annealed at an almost equal temperature of 600 °C. Atomic-scale observation using a high-angle annular dark-field (HAADF) method distinctly showed the existence of the L21-ordered regions in the B2-ordered matrix in the upper Co2MnSi electrode annealed at 400 °C. 相似文献
85.
Masao Takahashi Takeru Shishido Hitoo Iwasa Hikaru Kobayashi 《Central European Journal of Physics》2009,7(2):227-231
The local photovoltage of the pn-junction single-crystalline silicon solar cells observed by spot light scanning gradually
decreases in the vicinity of edges. The energy conversion efficiency is increased by shadowing the edge regions where the
local photovoltage is lower, showing that the defect density is high in the edge regions. From the analysis of the local photovoltage,
the spacial distribution of defect states is obtained. The cyanide method, i. e., immersion of solar cells in HCN solutions at room temperature, increases the local photovoltage and increases the energy
conversion efficiency.
相似文献
86.
87.
Transition of the radial electric field by electron cyclotron heating in the CHS heliotron/torsatron
88.
89.
H. Takahashi N. Mri Y. Nagata S. Nakamura T. Uchida J. Akimitsu Y. Tokura 《Physica C: Superconductivity and its Applications》1993,210(3-4):485-488
The superconducting transition temperature (Tc) of Ba0.62K0.38Bio3 (Tc=30 K) has been measured under high pressure up to 8 GPa. It is observed that Tc increases initially with pressure, as reported by Uwe et al., Shirber et al. and Huang et al., but decreases above 4 GPa. The Hall coefficient of Ba0.62K0.38BiO3 has been measured up to 1.2 GPa. The absolute value of the Hall coefficient decreases with pressure by 10% GPa, the value of which is almost the same as that obtained in most CuO-based high-temperature superconductors. 相似文献
90.
Optical band gap of Zn3N2 films 总被引:1,自引:0,他引:1