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21.
Cho T Yoshida M Kohagura J Hirata M Numakura T Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Nakashima Y Saito T Tatematsu Y Yoshikawa M Kojima Y Tokioka S Yokoyama N Tomii Y Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2005,94(8):085002
Vortexlike turbulent structures in hot-ion mode plasmas with several keV are observed in the case with a radially produced weak shear of electric fields E(r). However, a strong E(r) shear formation due to a high ion-confining potential phi(c) production clears up these vortices together with plasma-confinement improvement and disappearance of both drift-wave and turbulencelike Fourier spectral signals. These findings are based on three-time progress in phi(c) in comparison to phi(c) attained 1992-2002. The significant advance of phi(c) is well extended in line with proposed potential-formation physics scalings. 相似文献
22.
T Sato H Yokoyama H Ohya H Kamada 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2001,153(1):113-116
An imaging technique of electrically detected magnetic resonance (EDMR) was newly developed. Because the EDMR signal is obtained from paramagnetic recombination centers, one may expect the image to represent the distribution of defect and/or impurity sites in the sample. We successfully obtained EDMR images of a light-illuminated silicon plate 8 mm in width and 15 mm in length, which was cut from a silicon wafer (n-type, 100 Omega cm), under ESR irradiation at a frequency of 890 MHz (wavelength, 340 mm). The reproducibility of the EDMR image obtained from a sample was amply satisfactory. When the oxidized surface of the silicon was removed, the EDMR signal disappeared. Although the EDMR signal reappeared when the surface of the sample became reoxidized, the EDMR image obtained was slightly different from the earlier one. This finding shows that the EDMR image obtained from the sample shows the distribution of defects at the Si/SiO(2) interface. 相似文献
23.
Ida K Funaba H Kado S Narihara K Tanaka K Takeiri Y Nakamura Y Ohyabu N Yamazaki K Yokoyama M Murakami S Ashikawa N deVries PC Emoto M Goto M Idei H Ikeda K Inagaki S Inoue N Isobe M Itoh K Kaneko O Kawahata K Khlopenkov K Komori A Kubo S Kumazawa R Liang Y Masuzaki S Minami T Miyazawa J Morisaki T Morita S Mutoh T Muto S Nagayama Y Nakanishi H Nishimura K Noda N Notake T Kobuchi T Ohdachi S Ohkubo K Oka Y Osakabe M Ozaki T Pavlichenko RO Peterson BJ Sagara A Saito K Sakakibara S Sakamoto R 《Physical review letters》2001,86(23):5297-5300
Recent large helical device experiments revealed that the transition from ion root to electron root occurred for the first time in neutral-beam-heated discharges, where no nonthermal electrons exist. The measured values of the radial electric field were found to be in qualitative agreement with those estimated by neoclassical theory. A clear reduction of ion thermal diffusivity was observed after the mode transition from ion root to electron root as predicted by neoclassical theory when the neoclassical ion loss is more dominant than the anomalous ion loss. 相似文献
24.
Kosaka H Shigyou H Mitsumori Y Rikitake Y Imamura H Kutsuwa T Arai K Edamatsu K 《Physical review letters》2008,100(9):096602
We demonstrate that the superposition of light polarization states is coherently transferred to electron spins in a semiconductor quantum well. By using time-resolved Kerr rotation, we observe the initial phase of Larmor precession of electron spins whose coherence is transferred from light. To break the electron-hole spin entanglement, we utilized the big discrepancy between the transverse g factors of electrons and light-holes. The result encourages us to make a quantum media converter between flying photon qubits and stationary electron-spin qubits in semiconductors. 相似文献
25.
H. Matsubara M. Takaki T. Uesaka S. Shimoura N. Aoi M. Dozono T. Fujii K. Hatanaka T. Hashimoto T. Kawabata S. Kawase K. Kisamori Y. Kikuch Y. Kubota C. S. Lee H. C. Lee Y. Maeda S. Michimasa K. Miki H. Miya S. Noji S. Ota S. Sakaguchi Y. Sasamoto T. Suzuki L. T. Tang K. Takahisa H. Tokieda A. Tamii K. Yako Y. Yasuda N. Yokota R. Yokoyama J. Zenihiro 《Few-Body Systems》2013,54(7-10):1433-1436
Spectroscopy for neutron-rich nuclei 9He and 12Be has been performed by means of heavy-ion double charge exchange (HIDCX) (18O, 18Ne) reaction on stable target nuclei 9Be and 12C, respectively. Several clear peaks in 12Be at low excitation energy region even above neutron separation energy have been observed in one-shot measurement, whereas no prominent signals of 9He have been observed owing to the small cross section. It is shown that the HIDCX reaction is a new powerful spectroscopic tool for study of unstable neutron-rich nuclei. 相似文献
26.
Low-noise operation of a 9-GHz hybridly mode-locked laser diode is demonstrated. The integrated timing jitter was 47 fs (10 Hz to 10 MHz) and 86 fs (10 Hz to 4.5 GHz), with a pulse width of 6.7 ps. The noise performance as a function of filter bandwidth and oscillator noise is also addressed. 相似文献
27.
We study the local density of states at the surface of a chiral p-wave superconductor in the presence of a weak magnetic field. As a result, the formation of low-energy Andreev bound states is either suppressed or enhanced by an applied magnetic field, depending on its orientation with respect to the chirality of the p-wave superconductor. Similarly, an Abrikosov vortex, which is situated not too far from the surface, leads to a zero-energy peak of the density of states, if its chirality is the same as that of the superconductor, and to a gap structure for the opposite case. We explain the underlying principle of this effect and propose a chirality sensitive test on unconventional superconductors. 相似文献
28.
Yokoyama H 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2012,214(1):119-123
Direct irradiation of a sample using a quartz oscillator operating at 250 MHz was performed for EPR measurements. Because a quartz oscillator is a frequency fixed oscillator, the operating frequency of an EPR resonator (loop-gap type) was tuned to that of the quartz oscillator by using a single-turn coil with a varactor diode attached (frequency shift coil). Because the frequency shift coil was mobile, the distance between the EPR resonator and the coil could be changed. Coarse control of the resonant frequency was achieved by changing this distance mechanically, while fine frequency control was implemented by changing the capacitance of the varactor electrically. In this condition, EPR measurements of a phantom (comprised of agar with a nitroxide radical and physiological saline solution) were made. To compare the presented method with a conventional method, the EPR measurements were also done by using a synthesizer at the same EPR frequency. In the conventional method, the noise level increased at high irradiation power. Because such an increase in the noise was not observed in the presented method, high sensitivity was obtained at high irradiation power. 相似文献
29.
Supawan Joonwichien Eiji Yamasue Hideyuki Okumura Keiichi N. Ishihara 《Applied magnetic resonance》2012,42(1):17-28
Magnetic field effects (MFEs) on photocatalytic degradation of methylene blue (MB) solution over ZnO and TiO2 powders are investigated under static magnetic field up to 0.7 T with light irradiation by ultraviolet (UV) light emitting diode. The UV–visible-near-infrared spectrometer is used to monitor the MB concentrations. The positive MFE is observed for ZnO, while the negative MFE for TiO2, and both MFEs are increased with the increase in the magnetic field applied. By increasing the settling time (the time interval between the preparation of MB solution and the powder dispersion into the MB solution), the photodegradation abilities under MFEs are decreased for both the catalysts. The cause of MFE is discussed in terms of dissolved oxygen in the MB solution and magnetic adsorption of the constituent molecules. 相似文献
30.