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101.
Y. Bruynseraede T. Puig E. Rosseel M. Baert M. J. Van Bael K. Temst V. V. Moshchalkov R. Jonckheere 《Journal of Low Temperature Physics》1997,106(3-4):173-182
We have studied the superconducting properties of antidot arrays and mesoscopic antidot clusters near the superconducting-normal
phase boundary. Characteristic minima and maxima have been observed in the magnetore-sistance, critical current and phase
boundary caused by the formation of stable vortex configurations at the antidots. A comparison with a simple theoretical model
has shown that the effects in the arrays as well as in the clusters originate from quantization of the fluxoid at the antidots.
This model has enabled an identification of all vortex configurations. 相似文献
102.
Raul Jimenez Zambrano Francisco A. Rubinelli Wim M. Arnoldbik Jatindra K. Rath Ruud E. I. Schropp 《Solar Energy Materials & Solar Cells》2004,81(1):73-86
A new band gap profile (exponential profile) for the active layer of the a-SiGe:H single junction cell has been designed and experimentally demonstrated. By computer simulations we show how bending the grading of the band gap in the i-layer contributes to the enhancement of the carrier collection, improving the fill factor and efficiency. The differences observed between experiments and simulations are studied using Rutherford Backscattering Spectrometry (RBS). The results highlight weak points during the deposition process, whose control enables us to bring together experimental and computational results. 相似文献
103.
104.
105.
光纤激光器的研究与发展 总被引:2,自引:0,他引:2
介绍光纤激光器的工作原理、分类以及为消除激射过程中的许多不利因素,提高光束质量而采取的技术措施,同时介绍近几年同内外光纤激光器的研究与发展。 相似文献
106.
Dual-band infrared detectors made on high-quality HgCdTe epilayers grown by molecular beam epitaxy on CdZnTe or CdTe/Ge substrates 总被引:2,自引:0,他引:2
P. Ballet F. Noël F. Pottier S. Plissard J. P. Zanatta J. Baylet O. Gravrand E. De Borniol S. Martin P. Castelein J. P. Chamonal A. Million G. Destefanis 《Journal of Electronic Materials》2004,33(6):667-672
In this paper, we present all the successive steps for realizing dual-band infrared detectors operating in the mid-wavelength
infrared (MWIR) band. High crystalline quality HgCdTe multilayer stacks have been grown by molecular beam epitaxy (MBE) on
CdZnTe and CdTe/Ge substrates. Material characterization in the light of high-resolution x-ray diffraction (HRXRD) results
and dislocation density measurements are exposed in detail. These characterizations show some striking differences between
structures grown on the two kinds of substrates. Device processing and readout circuit for 128×128 focal-plane array (FPA)
fabrication are described. The electro-optical characteristics of the devices show that devices grown on Ge match those grown
on CdZnTe substrates in terms of responsivity, noise measurements, and operability. 相似文献
107.
测量了硫酸介质中Ge在硅胶上的分配比及Ga、Cu、Zn在硅胶上的吸附。研究了硫酸浓度、Ga浓度及原始溶液中Ge载体量对Ge分配比的影响。实验结果表明:用10mm×30mm硅胶柱,上柱料液为50mL0.4μg/mLGe-0.28mol/LGa-9mol/LH2SO4溶液,淋洗液为30mL9mol/LH2SO4,流速为0.85mL/cm2·min时,Ge的穿透率为0.39%,Ga、Cu、Zn的去污系数分别为1.8×106、5.0×106、2.6×106。 相似文献
108.
As a first step towards developing heterostructures such as GaAs/Ge/Si entirely by chemical vapor deposition, Ge films have
been deposited on (100) Si by the pyrolysis of GeH4. The best films are grown at 700° C and are planar and specular, with RBS minimum channeling yields of ≈4.0% (near the theoretical
value) and defect densities of 1.3 x 108 cm−2. Variations of in-situ cleaning conditions, which affect the nature of the Si substrate surface, greatly affect the ability
to get good epitaxial growth at 700° C. The majority of the defects found in the Ge films are extrinsic stacking faults, formed
by dissociation of misfit and thermal expansion accommodation dislocations. The stacking fault density is not significantly
reduced by post-deposition annealing, as is the case for the dislocations observed in MBE Ge films. It is suggested that lowering
the CVD growth temperature through the use of high vacuum deposition equipment would result in dislocation defects like those
of MBE films which could then be annealed more effectively than stacking faults. Films with defect densities equivalent to
MBE Ge films (~2 x 107 cm−2) could then probably be produced. 相似文献
109.
D. Kumar R. D. Vispute O. Aboelfotoh S. Oktyabrsky K. Jagannadham J. Narayan P. R. Apte R. Pinto 《Journal of Electronic Materials》1996,25(11):1760-1766
Metallization of high-Tc superconductors using low resistivity metal oxides and Cu-Ge alloys has been investigated on high quality pulsed laser deposited
epitaxial YBa2Cu3O7-x (YBCO) films. Epitaxial LaNiO3 (LNO) thin films have been grown on YBCO films at 700°C using pulsed laser deposition. The specific resistivity of LNO was
measured to be 50 μΩ-cm at 300K which decreases to 19 μΩ-cm at 100K indicating good metallicity of the LNO films. The contact
resistance of LNO-YBCO thin film interface was found to be reasonably low (of the order of 10-4Ω-cm2 at 77K) which suggests that the interface formed between the two films is quite clean and LNO can emerge as a promising metal
electrode-material to YBCO films. A preliminary investigation related to the compatibility of Cu3Ge alloy as a contact metallization material to YBCO films is discussed. The usage of other oxide based low resistivity materials
such as SrRuO3 (SRO) and SrVO3 (SVO) for metallization of high-Tc YBCO superconductor films is also discussed. 相似文献
110.
Large single crystals of Pb1-xGexTe (0 < × < 0.105) up to 10 g and Pb1-ySnyTe (0 < y < 0.26) up to 125 g were grown in sealed
tubes by self-transport onto oriented single crystal seeds. The crystals were free of voids and inclusions, had dislocation
densities as low as 103 cm-2, and were uniform in composition. Pertinent details of the growth technique, including thermal
conditions, stoichiometry of the source, and seed orientation, are described. Results of evaluation of the crystals by metallography,
Laue X-ray topography, and electron microprobe analysis are presented. 相似文献