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	Preparation, characterization and optical properties of carbon doped ZnO nanocrystal (EI CONFERENCE) 会议论文 OAI收割 ICO20: Materials and Nanostructures, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu J.; Liu J.; Liu J.; Li S.; Wang Z. 收藏 \| 浏览/下载：29/0 \| 提交时间：2013/03/25 In this paper we prepared carbon doped nanocrystalline ZnO by pyrolyzed zinc stearate at 250C and 300C respectively. The XRD curves indicate the sample has polycrystalline hexagonal wurtzite structure. The XRD data of the sample prepared at 250C and 300C has a bigger angle shift about 0.05and 0.3respectively. That indicate the structure of the sample has some changes. The EDS indicate the sample contains Zn O and C. So the XRD shift may attribute to the C. The XPS indicate the C doped in the crystal lattice of ZnO of the sample prepared at 300C and the sample prepared at 250C may be only a few of C doped in the crystal lattice of ZnO. The PL of the sample prepared at 300C only has a weak ultraviolet emission which indicates C modified the nanocrystalline ZnO surface as a non-radiative recombination center. In this process C could non-radiatively recombine the carries on the nanocrystallin ZnO surface. The sample prepared at 250C has a strong visible emission at about 530 nm. This emission band could be attributed to oxygen vacancy because C schlepped some oxygen on the nanocrystalline ZnO surface.
	Effect of interface on luminescence properties in ZnO/MgZnO heterostructures (EI CONFERENCE) 会议论文 OAI收割 Wei Z. P.; Lu Y. M.; Shen D. Z.; Wu C. X.; Zhang Z. Z.; Zhao D. X.; Zhang J. Y.; Fan X. W. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 A set of ZnO/MgZnO heterostructures with well widths Lw varying from 2 to 20 nm has been grown by plasma-assisted molecular-beam epitaxy (P-MBE). We present a room-temperature (RT) study of the well-width-dependent photoluminescence (PL) spectra and carrier lifetimes in ZnO/MgZnO heterostructures. Bi-exponential process is seen at RT time-decay curves of the luminescence from the well layers. The fast process is from the recombination of the free exciton while the slow process is attributing to the recombination of the localized exciton in the interface of ZnO and MgZnO. It is also confirmed from the PL peak shift of time-resolved PL spectra. With decreasing the well thickness the fast process gradually increases and dominantly contributes to the PL spectrum due to the interface improvement. 2006 Elsevier B.V. All rights reserved.
	Excitonic properties of vertically aligned ZnO nanotubes under high-density excitation (EI CONFERENCE) 会议论文 OAI收割 Lu Y. M.; Liang H. W.; Shen D. Z.; Zhang Z. Z.; Zhang J. Y.; Zhao D. X.; Liu Y. C.; Fan X. W. 收藏 \| 浏览/下载：13/0 \| 提交时间：2013/03/25 In this paper highly oriented and vertically arranged ZnO nanotubes are prepared on Al2O3 (0 0 0 1) substrate without employing any metal catalysts by plasma-assisted molecular beam epitaxy. The photoluminescence (PL) spectra at room temperature are studied under high excitation densities. Under lower excitation density (60 kW/cm2) PL spectrum shows that one strong free exciton emission (FE) locates at 3.306 eV. As the excitation density increases up to 200 kW/cm2 a new emission peak (Pn) located at low-energy side of FE is attributed to the spontaneous emission due to an exciton-exciton (Ex-E x) scattering process from two ground state excitons where one exciton is recombined by emitting a photon and the other is scattered into the excited states of n=2 3 4.... Under excitation density of 300 kW/cm 2 the stimulated emission originating from Ex-E x scattering is obtained. When the excitation density is above 580 kW/cm2 the emission from electron-hole plasma is observed in low-energy side of the P band and indicates a typical superradiation recombination processes with increasing excitation density. 2006 Elsevier B.V. All rights reserved.
	Field emission properties of ZnO nanowires (EI CONFERENCE) 会议论文 OAI收割 ICO20: Display Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China Meng X. Q.; Shen D. Z.; Zhang J. Y.; Zhao D. X.; Lu Y. M.; Zhang Z. Z.; Fan X. W. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 ZnO nanowires were obtained by using a simple vapor solid process. The length of the nanowires is about 1 m with diameters ranging from 40 nm to 150 nm. X-ray diffraction (XRD) pattern confirms the nanowires are wurtzite structure with c-axis preferred orientation. Photoluminescence (PL) measurement shows a strong UV emission and a weak visible emission. Field emission (FE) results proved the nanowires have low turn-on voltage and high field enhancement factor which indicates ZnO nanowire is a suitable candidate for field emission display.
	Characterization of ZnO/Mg0.12Zn0.88O heterostructure grown by plasma-assisted molecular beam epitaxy (EI CONFERENCE) 会议论文 OAI收割 13th International Conference on Molecular Beam Epitaxy, August 22, 2004 - August 27, 2004, 13th International Conference on Molecular Beam Epitaxy, August 22, 2004 - August 27, 2004 Lu Y. M.; Wu C. X.; Wei Z. P.; Zhang Z. Z.; Zhao D. X.; Zhang J. Y.; Liu Y. C.; Shen D. Z.; Fan X. W. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 In this paper Mg0.12Zn0.88O/ZnO heterostructures were fabricated on c-plane sapphire (Al2O3) substrates by plasma-assisted molecular beam epitaxy (P-MBE). The quality of the Mg 0.12Zn0.88O alloy thin film was characterized by X-ray diffraction (XRD) and reflection high-energy electron diffraction (RHEED). Optical properties of the Mg0.12Zn0.88O/ZnO heterostructure were studied by absorption and photoluminescence (PL) spectra. At room temperature (RT) Mg0.12Zn0.88O/ZnO heterostructures show two absorption edges originating from ZnO and Mg 0.12Zn0.88O layers respectively. In PL spectra two ultraviolet emission bands related to the ZnO layer and the Mg 0.12Zn0.88O layer were observed. The emission band from Mg0.12Zn0.88O layer dominates at moderately lower temperature and the luminescence of ZnO becomes gradually important with increasing temperature. This is suggested to exist as a potential barrier in the interface and to restrict the relaxation of the carriers from the Mg 0.12Zn0.88O layer to ZnO layer. As the thickness of ZnO layer decreases the emission from the Mg0.12Zn0.88O layer becomes weaker and weaker. When the ZnO thickness is up to 2 nm only the luminescence of the ZnO layer is observed at RT. The quenching of the emission corresponding to the MgZnO layer indicates the existence of a strong injection process in the samples with thinner ZnO layer. 2005 Elsevier B.V. All rights reserved.
	Asymptotic behavior of the Lipschitz-1/2 modulus of the PL-process for truncated and censored data 期刊论文 OAI收割 ACTA MATHEMATICA SINICA-ENGLISH SERIES, 2003, 卷号: 19, 期号: 4, 页码: 729-738 作者: Zhou, Y; Wu, GF; Jiang, XL \| 收藏 \| 浏览/下载：18/0 \| 提交时间：2018/07/30 truncated and censored data oscillation inodulus Lipschitz-1/2 modulus PL-process cumulative hazard process Law of the iterated logarithrn
	Strong limit theorems for oscillation moduli of PL-process and cumulative hazard process under truncation and censorship with applications 期刊论文 OAI收割 ACTA MATHEMATICA SINICA-ENGLISH SERIES, 1999, 卷号: 15, 期号: 2, 页码: 235-244 作者: Sun, LQ; Zhou, Y \| 收藏 \| 浏览/下载：24/0 \| 提交时间：2018/07/30 truncation and censorship oscillation modulus PL-process cumulative hazard process kernel estimator