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51.
Formation of p-type ZnO film on InP substrate by phosphor doping 总被引:3,自引:0,他引:3
Kyu-Hyun Bang Deuk-Kyu Hwang Min-Chul Park Young-Don Ko Ilgu Yun Jae-Min Myoung 《Applied Surface Science》2003,210(3-4):177-182
ZnO thin film was initially deposited on InP substrate by radio frequency (rf) magnetron sputtering and the diffusion process was performed using the closed ampoule technique where Zn3P2 was used as the dopant source. To verify the junction formation of ZnO thin films, the electrical properties were measured, and the effects of Zn3P2 diffusion on ZnO thin films were investigated. It is observed that the electrical property of the film is changed from n-type to p-type by dopant diffusion effect. Based on the results, it is confirmed that ZnO thin films can be a potential candidate for ultraviolet (UV) optical devices. 相似文献
52.
Beom-Ki ShinTae-Il Lee Ji-Hyeon ParkKang-Il Park Kyung-Jun AhnSung-Kee Park Woong LeeJae-Min Myoung 《Applied Surface Science》2011,258(2):834-838
Applicability of Ga-doped ZnO (GZO) films for thin film solar cells (TFSCs) was investigated by preparing GZO films via pulsed dc magnetron sputtering (PDMS) with rotating target. The GZO films showed improved crystallinity and increasing degree of Ga doping with increasing thickness to a limit of 1000 nm. The films also fulfilled requirements for the transparent electrodes of TFSCs in terms of electrical and optical properties. Moreover, the films exhibited good texturing potential based on etching studies with diluted HCl, which yielded an improved light trapping capability without significant degradation in electrical propreties. It is therefore suggested that the surface-textured GZO films prepared via PDMS and etching are promising candidates for indium-free transparent electrodes for TFSCs. 相似文献
53.
Chi-Yee Cheung Chien-Wen Hwang Wei-Min Zhang 《Zeitschrift fur Physik C Particles and Fields》1997,75(4):657-664
A consistent treatment of B → πlν decay is given on the light-front. The B to π transition form factors are calculated in the entire physical range of momentum transfer for the first time. The valence-quark contribution is obtained using relativistic light-front wave functions. Higher quark-antiquark Fock-state of the B-meson bound state is represented effectively by the ¦B*π〉 configuration, and its effect is calculated in the chiral perturbation theory. Wave function renormalization is taken into account consistently. The ¦B*π〉 contribution dominates near the zero-recoil point (q 2 ? 25 GeV2), and decreases rapidly as the recoil momentum increases. The calculated form factor ?+(q 2) follows approximately a dipole q 2-dependence in the entire range of momentum transfer. We estimate that ¦V ub¦=0.003. 相似文献
54.
ZHU Sheng-Jiang J.H. Hamilton A.V. Ramayya J.K. Hwang J.O. Rasmussen Y. X. Luo K. Li WANG Jian-Guo CHE Xing-Lai DING Huai-Bo S. Frauendorf V. Dimitrov XU Qiang GU Long YANG Yun-Yi 《中国物理C(英文版)》2009,33(Z1)
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
55.
Sarira Sahu W.-Y. P. Hwang 《The European Physical Journal C - Particles and Fields》2008,58(4):609-615
We have calculated the effective potential experienced by highly relativistic neutrinos in a weakly magnetized electron–positron
plasma, where a momentum-dependent finite-width correction to the propagator of W is considered to account for the threshold effect. Magnetars are believed to be sources of TeV–PeV neutrinos which are produced
due to photomeson and proton–proton interactions in their atmosphere. We have studied the resonant-oscillation process ν
e
↔
ν
μ,τ
of the highly relativistic neutrinos in the atmosphere of SGR 1806-20, which is a magnetar. It is shown that, for high-energy
neutrinos propagating within the magnetar atmosphere, the resonance condition can never be satisfied. On the other hand, if
GeV neutrinos are produced deep inside the magnetar atmosphere, where the temperature is about 50 keV or more, then these
neutrinos can undergo resonant oscillation. 相似文献
56.
In this paper, we propose a method that controls the depth of the three-dimensional (3D) object existing over the depth-of-focus in integral imaging. The depth control method is performed only in a computer by synthesizing the intermediate sub-images between original sub-images obtained by transforming the captured elemental images. In the reconstruction process, we can obtain reconstructed 3D images with the better image quality within depth-of-focus than that reconstructed over the depth-of-focus. To demonstrate the feasibility of our method, optical and computational experiments are carried out and its results are presented. 相似文献
57.
Abstract
Large eddy simulation was performed to visualize the three-dimensional vortical structures interacting with a turbulent premixed in a lean premixed swirl combustor with varied equivalence ratio. It was found that the fluctuation of unsteady heat release due to the deformation of flame surface was significantly decreased as the equivalence ratio increased because of the change in interaction between inner vortical structures and flames. This phenomenon was another evidence of the amplification mechanism in the combustion instabilities due to the strong flame–vortex interactions under lean premixed conditions. 相似文献58.
Chih-Hung Chang Tzonelih Hwang Prosanta Gope 《International Journal of Theoretical Physics》2016,55(4):2125-2138
This article proposes a collective-noise resistant QPC protocol with the help of an almostdishonest third party (TP) who may try to perform any sort of attacks to derive participants’ private secrets except colluding with any participant. The proposed scheme has some considerable advantages over the state-of-the-art QPC protocols over collective-noise channels, where it does not require any pre-shared key between the participants (Alice and Bob). Nevertheless, the proposed scheme can resist Trojan horse attacks without consuming half of the transmitted qubits and any additional equipment (wavelength filter and PNS) support. As a consequence, the proposed QPC protocol can guarantee higher qubit efficiency as compared to the others over collective noise channels. 相似文献
59.
Yu. N. Yuryev Hwack‐Joo Lee Ju‐Hwang Kim Yang‐Koo Cho Min‐Kyu Lee K. Ju. Pogrebitsky 《X射线光谱测定》2008,37(5):476-481
A laboratory surface x‐ray absorption near edge structure ((S)XANES) spectrometer used for measurements in the soft x‐ray region is described. The x‐ray beam path of the spectrometer is enclosed in a vacuum chamber directly connected to the x‐ray generator output port. With this setup, the absorption of the x‐rays in the air is avoided. The developed spectrometer uses a monochromator equipped with cylindrically bent PET(002), KAP(001), and Ge(111) crystals of different Rowland radii working in the Johann focusing geometry. Nine stepping motors are used to control the positions of the monochromator, receiving slit, sample, and detectors. An x‐ray photon energy available in experiment ranges from about 1 keV to 5 keV. A registration of the photoelectrons emitted from the sample with the channeltron is used to carry out surface‐sensitive measurements. The performance of the developed spectrometer is illustrated by spectra measured at the absorption K‐edges of several elements from the Na‐Ti set. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
60.
The grand partition functions Z(T,B) of the Ising model on L×L triangular lattices with fully periodic boundary conditions, as a function of temperature T and magnetic field B , are evaluated exactly for L<12 (using microcanonical transfer matrix) and approximately for L?12 (using Wang–Landau Monte Carlo algorithm). From Z(T,B), the distributions of the partition function zeros of the triangular-lattice Ising model in the complex temperature plane for real B≠0 are obtained and discussed for the first time. The critical points aN(x) and the thermal scaling exponents yt(x) of the triangular-lattice Ising antiferromagnet, for various values of x=e−2βB, are estimated using the partition function zeros. 相似文献