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101.
吴鹏 《原子与分子物理学报》2023,40(6):062002-78
本文采用分子束外延技术,通过对金属分子束的精确控制,在MgO(002)基底上成功生长了GaxN2∶Zn3-x合金薄膜.高分辨率单晶X光衍射仪表征结果表明GaxN2∶Zn3-x合金薄膜仍是以(400)Zn3N2为主导的复合晶体结构,对衍射数据的分析得到该薄膜晶粒尺寸小.用扫描电子显微镜和能谱射线分析仪对其表面和成分做了深入的分析和讨论,在固定的金属流量比的生长环境下,不同厚度的样品在成膜后x均为0.65,化学通式Zn2.35Ga0.65N2.该结果表明Ga元素属于重度掺杂,同时也体现了分子束外延技术在共掺杂技术中的优越性.本文也测量并讨论了Zn2.35Ga0.65N2薄膜的光学性能,实验得到的1.85 eV的光学带隙与理论推算基本吻合,说明Ga的掺入有Ga-N结构... 相似文献
102.
Highly transparent N-doped ZnO thin films were deposited on ITO coated corning glass substrate by sol–gel method. Ammonium nitrate was used as a dopant source of N with varying the doping concentration 0, 0.5, 1.0, 2.0 and 3.0 at%. The DSC analysis of prepared NZO sols is observed a phase transition at 150 °C. X-ray diffraction pattern showed the preferred (002) peak of ZnO, which was deteriorated with increased N concentrations. The transmittance of NZO thin films was observed to be ~88%. The bandgap of NZO thin films increased from 3.28 to 3.70 eV with increased N concentration from 0 to 3 at%. The maximum carrier concentration 8.36×1017 cm−3 and minimum resistivity 1.64 Ω cm was observed for 3 at% N doped ZnO thin films deposited on glass substrate. These highly transparent ZnO thin films can be used as a window layer in solar cells and optoelectronic devices. 相似文献
103.
Chris S. K. Mak Qing Yun Leung Chi Ho Li Wai Kin Chan 《Journal of polymer science. Part A, Polymer chemistry》2010,48(11):2311-2319
Low‐bandgap rhenium(I) complex with absorption onset at 795 nm in solution was tethered onto π‐conjugated polymer. The conjugated copolymer provides solution processability of the metallopolymer, and the pendant allows the low energy‐absorbing Re(I) complex units to be evenly distributed on the thin film. The copolymer tethered with low‐bandgap rhenium complex was synthesized by Suzuki cross‐coupling reaction. The metal‐free polymer ( poly‐1 ) tethered with functionalized intramolecular charge transfer dye, 2‐phenyl‐3‐pyridin‐2‐yl‐5,7‐di‐2‐thienylthieno[3,4‐b]pyrazine, exhibited high molecular weight, good film‐forming properties, and excellent solution processability. The pendants of the conjugated polymer possess donor–acceptor characters and broaden the absorption band. These pendants can function as bidentate ligands for metal chelation. The solubilizing groups on the monomers provide good solubility to the polymer even with high content of metal chelation. Upon the complexation with rhenium(I) pentacarbonyl chloride, the absorption spectrum of the resulting metallopolymer was further extended toward the near‐infrared region. Photovoltaic performances based on this metallopolymer have been studied. The design approach of these metallopolymers provides synthetic feasibility for coordinating wide range of metal ions on the pendant, and the resulting low‐bandgap polymer can be a potential candidate for light harvesting material in solar cell applications. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 2311–2319, 2010 相似文献
104.
S. Liu Z. Lin 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,53(3):301-306
By the multiple scattering method and the extended Mie
theory, we have calculated the photonic band structure of the
photonic crystals consisting of the dielectric spheres with
uniaxial/biaxial anisotropy. The results demonstrate that for fcc
lattice structure there exist two partial photonic band gaps which
does not appear in the isotropic case. Among them, the lower one,
lying between the second and the third bands,
exists in one third of the first Brillouin zone,
while the upper one, opening between the fourth and fifth bands,
can appear simultaneously in the rest two thirds of the first Brillouin zone.
The effects of anisotropy on the band structures are
studied as well, which suggests the biaxial anisotropy are much more
flexible than the uniaxial anisotropy in modulating the band
structures. 相似文献
105.
106.
107.
108.
Omnidirectional Single-negative Gap and in Fibonacci Sequences Composed of Single-negative Materials
Ting-yi Shang Hui-yun Zhang Yu-ping Zhang Peng Wang Jian-quan Yao 《International Journal of Infrared and Millimeter Waves》2007,28(8):671-676
The band structures of Fibonacci sequence composed of single-negative materials are studied with a transfer matrix method.
A new type of omnidirectional single-negative gaps is found in the Fibonacci sequence. In contrast to the Bragg gaps, such
an omnidirectional single-negative gap is insensitive to the incident angles and polarization, and is invariant upon the change
of the ratio of the thicknesses of two media. It is found that omnidirectional single-negative gap exists in the other Fibonacci
sequence, and it is rather stable and independence of the structure sequence. 相似文献
109.
Films of Mn1−x
Fe
x
Se (x = 0–0.45) solid solutions were flash-sputtered. We measured the transmission spectra of the films in the wavelength
range 200–1000 nm at room temperature. From these spectra, we calculated the absorption coefficients and determined the fundamental
absorption edge, the position of which is shifted from 2.65 eV in MnSe to 2.30 eV in solid solutions of compositions x = 0.20–0.45.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 1, pp. 136–138, January–February, 2007. 相似文献
110.