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排序方式: 共有822条查询结果,搜索用时 15 毫秒
1.
Hyper-parallel quantum information processing is a promising and beneficial research field. Herein, a method to implement a hyper-parallel controlled-phase-flip (hyper-CPF) gate for frequency-, spatial-, and time-bin-encoded qubits by coupling flying photons to trapped nitrogen vacancy (NV) defect centers is presented. The scheme, which differs from their conventional parallel counterparts, is specifically advantageous in decreasing against the dissipate noise, increasing the quantum channel capacity, and reducing the quantum resource overhead. The gate qubits with frequency, spatial, and time-bin degrees of freedom (DOF) are immune to quantum decoherence in optical fibers, whereas the polarization photons are easily disturbed by the ambient noise. 相似文献
2.
用分子动力学方法模拟了空位在金刚石近(001)表面的扩散过程,研究了温度对空位扩散的影响.结果表明,当温度为1000K左右时,位于近表面第二层上的空位开始向表面运动;当温度在1400—2000K时,空位完全扩散到表面.这与实验结果和其他计算结果符合得很好.同时发现,温度为1400—1800K时,空位的扩散经历了两次迁移运动,其分别对应了均方位移图中的两个极大值.在不施加任何约束的条件下得到了空位的动态扩散路径,空位在金刚石近(001)表面的扩散势垒约为042eV.并探讨了一定温度下空位数目增多及其不同排列
关键词:
金刚石
空位
扩散
分子动力学 相似文献
3.
Alignment of photon-induced L3 vacancies is studied in rare earth and highZ elements at energies of experimental interest, near thresholds to 60 keV, under nonrelativistic dipole approximation. Numerical
calculations of the matrix element are undertaken to produce theoretical data for comparison with the experimental findings.
The A2 values being s>0.1 at photoelectron energies <20 keV are certainly higher than 5–8% uncertainties quoted in experimental
results. Present findings are from a very basic model, hydrogen-like and can further be treated as reference to observe the
impact of screening, relativistic, multipole and retardation corrections to the model 相似文献
4.
J. H. Marsh S. A. Bradshaw A. C. Bryce R. Gwilliam R. W. Glew 《Journal of Electronic Materials》1991,20(12):973-978
Impurity induced disordering of GaInAs quantum well structures with barriers of AlGaInAs and of GaInAsP has been investigated
using boron and fluorine. The impurities were introduced by ion implantation followed by thermal annealing. Annealing unimplanted
P-based quaternary material at temperatures greater than 500° C caused a blue shift of the exciton peak. At annealing temperatures
greater than 650° C red shifts in the exciton peak of unimplanted Al-based quaternary material were observed. Boron implantation
caused small blue shifts of the exciton peak in both material systems at low annealing temperatures. Much larger blue shifts
were observed in the fluorine implanted samples. 相似文献
5.
R. Niebuhr K. H. Bachem U. Kaufmann M. Maier C. Merz B. Santic P. Schlotter H. Jürgensen 《Journal of Electronic Materials》1997,26(10):1127-1130
Oxygen doped GaN has been grown by metalorganic chemical vapor deposition using N2O as oxygen dopant source. The layers were deposited on 2″ sapphire substrates from trimethylgallium and especially dried
ammonia using nitrogen (N2) as carrier gas. Prior to the growth of the films, an AIN nucleation layer with a thickness of about 300? was grown using
trimethylaluminum. The films were deposited at 1085°C at a growth rate of 1.0 μm/h and showed a specular, mirrorlike surface.
Not intentionally doped layers have high resistivity (>20 kW/square). The gas phase concentration of the N2O was varied between 25 and 400 ppm with respect to the total gas volume. The doped layers were n-type with carrier concentrations
in the range of 4×1016 cm−3 to 4×1018 cm−3 as measured by Hall effect. The observed carrier concentration increased with increasing N2O concentration. Low temperature photoluminescence experiments performed on the doped layers revealed besides free A and B
exciton emission an exciton bound to a shallow donor. With increasing N2O concentration in the gas phase, the intensity of the donor bound exciton increased relative to that of the free excitons.
These observations indicate that oxygen behaves as a shallow donor in GaN. This interpretation is supported by covalent radius
and electronegativity arguments. 相似文献
6.
Jing Yang 《Applied Surface Science》2006,253(4):1988-1994
To use solar irradiation or interior lighting efficiently, we sought a photocatalyst with high reactivity under visible light. Nitrogen and carbon doping TiO2−x−yNxCy films were obtained by heating the TiO2 gel in an ionized N2 gas and then were calcined at 500 °C. The TiO2−x−yNxCy films have revealed an improvement over the TiO2 films under visible light (wavelength, 500 nm) in optical absorption and photocatalytic activity such as photodegradation of methyl orange. X-ray photoemission spectroscopy, infrared spectrum and UV-visible (UV-vis) spectroscopy were used to find the difference of two kinds of films. Nitrogen and carbon doped into substitutional sites of TiO2 has been proven to be indispensable for band-gap narrowing and photocatalytic activity. 相似文献
7.
E. A. Zheligovskaya 《Journal of Structural Chemistry》2003,44(5):827-835
A computer simulation of proton-ordered ice IX and its proton-disordered analog III (768 molecules, 90 K) was carried out by the molecular dynamics method using Poltev–Malenkov's potential. For ice IX, the differences in the dynamic characteristics of molecules with O(1) and O(2) are much wider than those in the case of ice III. The libration spectrum of ice IX has a number of distinct acute peaks, and the spectrum of ice III is strongly smoothed. These peculiarities are explained by the proton ordering of ice IX and disordering of ice III. The latter is responsible for the great differences in the short- and especially long-range environment of water molecules in ice crystals and hence for the presence of many molecules with different dynamic characteristics. Thus averaging over a large number of different vibrational spectra of molecules leads to a smoothed total spectrum in the case of the proton-disordered crystal modification of ice. 相似文献
8.
LaxBa1—xCoO3系导电陶瓷导电性研究 总被引:1,自引:1,他引:1
对LaxBa1-xCoO导电陶瓷的导电性及其导电机制进行了研究,在x=0.5mol处,导电陶瓷具有金属态导是性,在La0.5Ba0.5CoO3陶瓷中,存在着氧缺位和导电电子,并且此种导电陶瓷具有较高的电子和氧离子混合导电特性。 相似文献
9.
A. Yu. Manakov J. Lipkowski K. Suwinska M. Kitamura 《Journal of inclusion phenomena and macrocyclic chemistry》1996,26(1-3):1-20
Single crystal X-ray structures of clathrates of -[Ni(NCS)2(4-methylpyridine)4] with furan, tetrahydrofuran, benzene + ethanol, methylene chloride, and methylcellosolve as guests molecules are reported. The location of the guest molecule in the partially decomposed clathrate with methylene chloride was defined by X-ray diffraction and compared with the fully occupied one. The host lattices of all clathrates studied are tetragonal (I41/a) and do not differ significantly from typical -phase clathrates of [M(NCS)2(4-methylpyridine)4] (M = divalent metal cation). Arrangements of guest molecules represent different types of packing: one type of guest molecule occupies both possible types of positions, two different guest molecules occupy different positions, with only one type of positions occupied by one type of guest molecule. Possible stoichiometries of clathrates with -type lattices are discussed.Presented at the Sixth International Seminar on Inclusion Compounds, Istanbul, Turkey, 27–31 August 1995. 相似文献
10.
Xiaolei Li Zifeng Lin Na Jin Lei Sun Xiaojiao Yang Ying Liu 《Advanced functional materials》2023,33(20):2214667
Polyoxometalates are intriguing high-capacity anode materials for alkali-metal-ion storage due to their multi-electron redox capabilities and flexible structure. However, their poor electrical conductivity and high working voltage severely restrict their practical application. Herein, the dinuclear polyoxovanadate Sr2V2O7·H2O with unusually high electrical conductivity is reported as a promising anode material for lithium-ion batteries. During the initial lithiation process, the Sr2V2O7·H2O anode experiences an electrochemically induced crystalline-to-amorphous transition. The resulting amorphous structure provides high redox activity and fast reaction kinetics via reversible V4.9+/V2.8+ redox couple through the intercalation mechanism. Furthermore, when coupled with the LiFePO4 cathode, the strong V O bonds of the amorphous anode provide excellent structural stability, with the full-cell capable of performing >12 000 cycles with a capacity retention of 72%. Another advantage of Sr2xV2O7-δ·yH2O (0.5 ≤ x ≤ 1.0) is its composition adjustability, which enables delicately regulating the Sr vacancy content without destroying the structure. The defect Sr2xV2O7-δ·yH2O (x = 0.5) electrodes show significantly improved specific capacity and rate capability without sacrificing other key properties, delivering a high specific capacity of 479 mAh g-1 at 0.1 mA cm-2 and 41.9% of its capacity in 2 min. Overall, the preliminary study points the way forward for the facile preparation of high-quality polyoxometalates for advanced energy storage applications and beyond. 相似文献