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First-principles full-potential linearized-augmented-plane-wave (FP-LAPW) calculations have been carried out for δ-Pu (110) films up to seven layers. The layers have been studied at the non-spin-polarized-no-spin-orbit coupling (NSP-NSO), non-spin-polarized-spin-orbit coupling (NSP-SO), spin-polarized-no-spin-orbit coupling (SP-NSO), spin-polarized-spin-orbit coupling (SP-SO), antiferromagnetic-no-spin-orbit coupling (AFM-NSO), and antiferromagnetic-spin-orbit-coupling (AFM-SO) levels of theory. The ground state of δ-Pu (110) films is found to be at the AFM-SO level of theory and the surface energy is found to rapidly converge. The semi-infinite surface energy for δ-Pu (110) films is predicted to be 1.41 J/m2, while the magnetic moments show an oscillating behavior, gradually approaching the bulk value of zero with increase in the number of layers. Work functions indicate a strong quantum size effect up to and including seven layers. The work function of the seven-layer δ-Pu (110) film at the ground state is found to be 2.99 eV.  相似文献   

3.
High spin states in A ~ 110 neutron-rich 106Mo, 110Ru and 112Ru nuclei have been reinvestigated by measuring the prompt γ-rays from the spontaneous fission of 252Cf. Two similar sets of bands are observed to high spins in each of three nuclei. Through analyzing of characters of the band structures, the chiral doublet bands are suggested in 106Mo, 110Ru and 112Ru.  相似文献   

4.
The high spin states of neutron-rich 103Nb, 107Tc and 109Tc nuclei in A~110 region have been investigated by measuring prompt γ-γ-γ coincident measurements populated with the spontaneous fission of 252Cf with the Gammasphere detector array. In 103Nb, one-phonon K = 9/2 and two-phonon K = 13/2 γ-vibrational bands have been identified. In 107Tc and 109Tc, one-phonon K = 11/2 and two-phonon K = 15/2 γ-vibrational bands, in which the zero-phonon bands are based on K=7/2 excited states, have also been identified. The two-phonon bands are first observed in odd-Z nuclei. The characteristics for these band structures have been discussed.  相似文献   

5.
The high spin states of neutron-rich 103Nb, 107Tc and 109Tc nuclei in A~110 region have been investigated by measuring prompt γ-γ-γ coincident measurements populated with the spontaneous fission of 252Cf with the Gammasphere detector array. In 103Nb, one-phonon K = 9/2 and two-phonon K = 13/2 γ-vibrational bands have been identified. In 107Tc and 109Tc, one-phonon K = 11/2 and two-phonon K = 15/2 γ-vibrational bands, in which the zero-phonon bands are based on K=7/2 excited states, have also been identified...  相似文献   

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Focusing collisions along 110 directions in f. c. c. lattices are investigated. For small angular deviations from this direction an exact treatment of subsequent collisions is possible. The results are compared with machine calculations byVineyard and collaborators. The agreement is practically complete. The influence of neighbouring atomic chains can be neglected.  相似文献   

8.
We investigate theoretically the combination effect of an in-plane magnetic field and spin-orbit interactions (SOIs) on the spin and charge transport property of a quasi-one-dimensional quantum wire embedded in the (110) crystallographic plane. We find that the oscillations of the conductance induced by the SOIs become more significant and different for the spin-up and spin-down electrons in the presence of the in-plane magnetic field. The conductance exhibits a significant anisotropic behavior and electrons exhibit out-of-plane spin polarization which can be tuned by an in-plane magnetic field. These features offer us an efficient way to control SOI-induced spin transport using in-plane magnetic fields.  相似文献   

9.
《Radiation measurements》2000,32(3):247-252
We have investigated the gamma ray induced sensitization of the 110°C TL peak in quartz, separated from sand, in the dose range 30–750 Gy. A pre-dose of 100 Gy followed by annealing at 500°C for 1 h yielded an optimum sensitization factor of 14.2 for a test gamma dose of 0.5 Gy; this factor decreases slowly up to the studied pre-gamma dose of 750 Gy. From ESR studies carried out in the temperature range 25–550°C, the formation of E1-centres and their subsequent decay (at temperatures >400°C) have been observed. The released charge carriers (electrons) may lead to elimination of competitors (as a result of their filling up). Thus, the radiation-induced sensitization of the 110°C TL peak could be due to elimination of the competing deep traps.  相似文献   

10.
110 °C thermoluminescence (TL) peak in quartz is well known due to its pre-dose effect, which is used in dating technique. The generally accepted mechanism for the production of this peak is based on Ge impurity contained in quartz. Its role is to substitute for Si in SiO4 tetrahedron and under irradiation gives rise to [GeO4/e?]? electron centre. Heating for TL read out liberates electron that recombines with hole in [AlO4/h]° or [H3O4/h]° centres emitting photon. The investigation, carried out on blue quartz, green quartz, black quartz, pink quartz, red quartz, sulphurous quartz, milky quartz, alpha quartz and synthetic quartz, has shown that the 110 °C TL peak in all these varieties of quartz has no correlation with the respective Ge content. Electron paramagnetic resonance (EPR) measurements on any of these varieties of quartz revealed a signal with g1=2.0004, g2=1.9986 and g3=1.974 and this signal does not appear to correspond to any known EPR signals in alpha quartz. Furthermore, isothermal decay measurements are carried out on the above mentioned EPR signal and 110 °C TL peak in alpha, blue and green quartz. A close correlation has been observed in the decay behavior. A new mechanism is proposed based on an interstitial O? centre.  相似文献   

11.
《Solid State Communications》2002,121(9-10):509-512
Current theory [Fiz. Tekh. Popluprovodn. 20 (1986) 178; Sov. Phys. Semicond. 20 (1986) 110] indicates that the D'yakonov–Perel' (DP) mechanism is unable to cause spin dephasing in quantum well (QW) with [110] growth direction. We point out that this is no longer true when the many-body inhomogeneous broadening effect of the DP term is taken into account. Based on our many-body theory [J. Supercond. 14 (2001) 245], by solving the kinetic Bloch equations, we show that the DP term contributes to the spin dephasing in (110) QW. The spin dephasing is also compared with that in (100) QW.  相似文献   

12.
在目前的超重元素研究中,合成110号元素是最激动人心的课题之一。本文以如何探索合成110号元素为线索,讨论了核质量和稳定性、由实验和理论得到的启示以及尝试合成它的最新实验。  相似文献   

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The near-interface region of an epitaxial Ba0.3Sr0.7TiO3 thin film grown on LaAlO3 (001) was found to consist of a high density of ½?110? stacking faults bounded by partial dislocations. The stacking faults can extend over large distances (greater than 50 nm). Various possible atomic configurations of the faults were considered. The atomic structures of the faults were identified using high-resolution electron microscopy and simulation as well as energy-filtered imaging. The ½[101] and faults (where [001] is normal to the film plane) were found to lie predominately on the {100} and {110} planes. The ½lsqb;101] faults on (010), (110) or (1&1tilde;0) have never been observed before in perovskites. The stacking faults on [100] have a structure consisting of a double layer of edge-sharing TiO6 octahedra. The excess of Ti was detected by energy-filtered imaging. The formation of the extended stacking faults is probably related to a small amount of excess Ti during the film deposition, which may originate from the non-stoichiometry of the ceramic targets BaTiO3 and SrTiO3. It is also enhanced by the misfit-induced compressive strain in the early stages of the film growth.  相似文献   

15.
A key issue in metallic uranium and its related actinide compounds is the character of the f electrons, whether it is localized or itinerant.Here we grew well ordered uranium films on a W(110) substrate.The surface topography was investigated by scanning tunneling microscopy.The Fermi surface and band structure of the grown films were studied by angle-resolved photoemission spectroscopy.Large spectral weight can be observed around the Fermi level, which mainly comes from the f states.Additionally, we provided direct evidence that the f bands hybridize with the conduction bands in the uranium ordered films, which is different from previously reported mechanism of the direct f–f interaction.We propose that the above two mechanisms both exist in this system by manifesting themselves in different momentum spaces.Our results give a comprehensive study of the ordered uranium films and may throw new light on the study of the 5 f-electron character and physical properties of metallic uranium and other related actinide materials.  相似文献   

16.
57Fe NMR measurements with a Néel-type single crystal are described. The behaviour of the magnetic structure was calculated as function of the internal fieldH i. A clear distinction between wall and domain signals could be made. The corresponding relative enhancement factors w r (H i) and D r (H i) have been calculated and are in agreement with the measurements. The relaxation in the 90° Bloch walls is pure exponential. Both ratesT 1 –1 andT 2 –1 are proportional to w 2 (H i). The measurements make proof, that the 90° walls are folded inside the crystal.K.-H. König and H. Brömer, Verhandl. DPG(VI)22, I, AM-14.11 (1987)  相似文献   

17.
Results on inclusive ? production inK ? p interactions at 110 GeV/c are presented. The production cross section is found to be larger than in πp andpp interactions at similar energies, suggesting OZI allowed \(s\bar s\) fusion to be the dominant mechanism in ? production. Thex distributions of ? and \(\bar K^{*0} \) are found to be similar to each other over the entirex range suggesting an overall strangeness suppression factor of 0.20±0.04 in the sea to be the dominant source of the difference in the cross section for ? and \(\bar K^{*0} \) . There is no evidence of a narrowφπ ? state around 2.1 GeV/c2 as suggested byK + experiments, but there is some excess of events in the region 1.94?1.98 GeV/c2 consistent with theF-meson mass as observed ine + e ? experiments.  相似文献   

18.
发现111号和110号新元素德国重离子研究中心GSI的S.Hofmann和P.Armbuster等人组成的国际合作研究组(成员有GSI,俄罗斯杜布纳核研究所,斯洛伐克的Comenius大学和芬兰Jyvaskyla大学),于1994年12月17日(GS...  相似文献   

19.
张开明  叶令 《物理学报》1980,29(6):686-692
本文研究GaAs(110)面旋转弛豫的电子结构,采用一个原子集团来模拟GaAs(110)面,在其内边界上用一些“类Ga”和“类As”原子来钝化伸向体内的悬挂键,以消除由于有限模型而引起的多余边界效应。用EHT方法计算集团的总能量,由能量极小定出GaAs(110)面最稳定的弛豫位置为表面旋转角ω=18°,表面Ga原子向体内下降0.33?,As原子上升0.13?,这与Pandey等人从光电子部分产额谱所得的结果基本一致。本文还计算了理想和弛豫的GaAs(110)面的态密度,发现对于理想的(110)面禁带中确实存在一个空的表面峰。弛豫后,该峰向上移动进入导带,禁带中不再出现表面峰,与实验结果相符。 关键词:  相似文献   

20.
Theβ decay Ag110m→Cd110 has been investigated with a double lens spectrometer and aβ-γ circular-polarization correlation setup. The shape of the 6+→6+ β spectrum withE 0=529 keV was found to be allowed, in disagreement with earlier work. The constantA of theβ-γ circular-polarization correlation was measured to beA=0·07±0·02. This implies a ratioX of Fermi to Gamow-Teller contribution to the decay ofX 1=?0·02±0·03 orX 2=?10·3 ?4·1 +2·3 . Qualitative shell model considerations favor the valueX 1. Additional information is given for the disintegration schemes of Ag110m and Ag110.  相似文献   

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