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81.
We have observed the Fano-Kondo antiresonance in a quantum wire with a side-coupled quantum dot. In a weak coupling regime, dips due to the Fano effect appeared. As the coupling strength increased, conductance in the regions between the dips decreased alternately. From the temperature dependence and the response to the magnetic field, we conclude that the conductance reduction is due to the Fano-Kondo antiresonance. At a Kondo valley with the Fano parameter q approximately 0, the phase shift is locked to pi/2 against the gate voltage when the system is close to the unitary limit in agreement with theoretical predictions by Gerland et al. [Phys. Rev. Lett. 84, 3710 (2000)]. 相似文献
82.
Spatiotemporal correlations of earthquakes are studied numerically on the basis of the one-dimensional spring-block (Burridge-Knopoff) model. As large events approach, the frequency of smaller events gradually increases, while, just before the mainshock, it is dramatically suppressed in a close vicinity of the epicenter of the upcoming mainshock, a phenomenon closely resembling the "Mogi doughnut." 相似文献
83.
Observation of "partial coherence" in an Aharonov-Bohm interferometer with a quantum dot 总被引:1,自引:0,他引:1
We report experiments on the interference through spin states of electrons in a quantum dot (QD) embedded in an Aharonov-Bohm (AB) interferometer. We have picked up a spin-pair state, for which the environmental conditions are ideally similar. The AB amplitude is traced in a range of gate voltage that covers the pair. The behavior of the asymmetry in the amplitude around the two Coulomb peaks agrees with the theoretical prediction that the spin-flip process in a QD is related to the quantum dephasing of electrons. These results constitute evidence of "partial coherence" due to an entanglement of spins in the QD and in the interferometer. 相似文献
84.
Luminescence channels of manganese-doped spinel 总被引:1,自引:0,他引:1
Ayana Tomita Kensuke Tanaka Masanobu Shirai Kouichirou Tanaka Eiichi Hanamura 《Journal of luminescence》2004,109(1):19-24
Two independent luminescence channels are observed from manganese-doped spinel Mn:MgAl2O4. The luminescence around 520 nm is assigned to transition from the lowest electronic excited state 4T1 to the ground state 6A1 of Mn2+ (3d)5 ion by analyzing the excitation spectrum and electron spin resonance measurement. The emission at 650 nm is triggered by the band edge excitation and is assigned similarly to the charge-transfer process associated with the manganese ion. 相似文献
85.
Taniguchi T Yamanaka K Sumioka H Yamazaki T Tabata Y Kawarazaki S 《Physical review letters》2004,93(24):246605
The extraordinary Hall resistivity rho(xy) and the magnetization M of a canonical spin glass AuFe (8 at.% Fe) were measured simultaneously as functions of temperature with the best care to the thermal and the magnetic field hysteresis. The data of rho(xy) show an anomaly at the spin glass transition temperature T(g) and have different zero field cooling (ZFC) and field cooling (FC) measurements below T(g). Moreover, the value of rho(xy)/M, which represents the chiral susceptibility of the system in the present case, also shows the difference between ZFC and FC measurements. The results are consistent with the predictions of the chirality scenario of canonical spin glasses by Kawamura. 相似文献
86.
We study theoretically the effect of deformed microelliptical cavities on lasing characteristics. We show that the transition of stationary lasing states from unidirectional rotational waves to a mixture of clockwise and anticlockwise rotational waves occurs when the shape of a disk is deformed to that of an ellipse. 相似文献
87.
Kawamura N Nagamine K Matsuzaki T Ishida K Nakamura SN Matsuda Y Tanase M Kato M Sugai H Kudo K Takeda N Eaton GH 《Physical review letters》2003,90(4):043401
A systematic experimental study on muon-catalyzed fusion was conducted using a series of solid deuterium and tritium mixtures. A variety of conditions were investigated, i.e., tritium concentrations from 20% to 70%, and temperatures from 5 to 16 K. With decreasing temperature, we observed an unexpected decrease in the muon cycling rate (lambda(c)) and an increase in the muon loss probability (W). The origins of these observed changes were interpreted by the temperature-dependence in the dt mu formation process for lambda(c) and that in the muon reactivation process after muon-to-alpha sticking for W. 相似文献
88.
S. Hayami T. Kawahara G. Juhász K. Kawamura K. Uehashi O. Sato Y. Maeda 《Journal of Radioanalytical and Nuclear Chemistry》2003,255(3):443-447
The magnetic properties of the spin-crossover compound, [Fe(qsal)2]NCSe·2DMSO (N-(8-quinolyl)-salicyladimine) (1), have been measured. We have discovered that the compound 1 exhibits a wide "thermal hysteresis loop" of 115 K (T1/2 = 324 K and T1/2 = 209 K) in the first cycle. Thermogravimetric analysis shows that solvent molecules of the compound 1 are removed at around 324 K. This means that the hysteresis loop observed for the first cycle is only an apparent one. Following the first loop, the compound 1 shows a spin-crossover in warming mode. The spin transition occurs at T1/2= 285 K and T1/2 = 209 K and the hysteresis width can be estimated to be 76 K, which is one of the largest values reported so far for spin-crossover compounds. It is thought that the cooperativity produced in the compound mainly arises from the intermolecular interactions between the quinoline and the phenyl rings. 相似文献
89.
Studer A Amrein S Matsubara H Schiesser CH Doi T Kawamura T Fukuyama T Ryu I 《Chemical communications (Cambridge, England)》2003,(10):1190-1191
4-[(Trimethylstannyl)diphenylsilyl]butanoyl radical, arising from the corresponding 3-(stannylsilyl)propyl radical and CO, undergoes an SHi reaction at Si with extrusion of trimethyltin radical to give silacyclopentanone. The parent 3-(stannylsilyl)propyl radical was also found to isomerize to (3-stannylpropyl)silyl radical via a 1,4-Sn shift from Si to C with a rate constant of 9.3 x 10(4) s-1 at 80 degrees C. Ab initio and DFT MO calculations support a front-side attack mechanism. 相似文献
90.
Oka H Ito Y Ikai Y Matsumoto H Kato K Yamamoto I Shimizu M Kawamura N Miyazaki Y Nojiri T Okumura M Ohmi S Sato T Mori G 《Journal of AOAC International》2001,84(2):350-353
A survey was conducted to determine the incidence of tetracycline antibiotic (TCAs) residues in the kidneys of slaughtered animals that did not pass inspection for human consumption by the Japanese Food Sanitation Law and the Meat Inspection Law at the slaughterhouses in Aichi Prefecture, Japan, from April 1985 to March 1998. The kidneys were analyzed by the AOAC Official Method 995.09. Among 424 animals (147 cattle and 277 pigs), 131 (30.9%) were contaminated with TCAs, including 69 (16.3%) with chlortetracycline (CTC), 61 (14.4%) with oxytetracycline (OTC), 3 (0.7%) with tetracycline (TC), and 1 (0.2%) with doxycycline (DC). One sample (cattle kidney) was contaminated with both OTC and DC. The frequencies of OTC and TC residues were significantly higher (p < 0.05) in cattle than in pigs, whereas, the frequency of CTC was significantly higher (p < 0.01) in pigs. Pig kidney samples collected in 1991-1997 had significantly higher incidences of TCAs and CTC (p < 0.01) residues than those in 1985-1986. 相似文献