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Bilayer superconducting films with tunable transition temperature(Tc) are a critical ingredient to the fabrication of high-performance transition edge sensors. Commonly chosen materials include Mo/Au, Mo/Cu, Ti/Au, and Ti/Al systems. Here in this work, titanium/indium(Ti/In) bilayer superconducting films are successfully fabricated on SiO_2/Si(001)substrates by molecular beam epitaxy(MBE). The success in the epitaxial growth of indium on titanium is achieved by lowering the substrate temperature to-150?C during indium evaporation. We measure the critical temperature under a bias current of 10 μA, and obtain different superconducting transition temperatures ranging from 645 m K to 2.7 K by adjusting the thickness ratio of Ti/In. Our results demonstrate that the transition temperature decreases as the thickness ratio of Ti/In increases. 相似文献
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通过制作亲碳性铟锡氧化物(ITO)/Ti复合电极,改善移植型碳纳米管(CNT)冷阴极的导电电极与CNT膜层之间附着性能,从而消除CNT与电极间的界面势垒和非欧姆接触对CNT阴极场发射均匀性和稳定性的影响.采用磁控溅射技术和丝网印刷工艺制作了ITO/Ti基CNT阴极.用X射线衍射仪和场致发射扫描电子显微镜表征CNT阴极结构,结果显示热处理后的ITO/Ti基CNT阴极中可能有TiC相生成,从而使得导电电极与CNT形成有中间物的强作用体系.该体系降低甚至消除电极与CNT之间的界面势垒,增加了CNT与电极间形成欧姆接触的概率.用四探针技术分析电阻率,结果表明ITO/Ti复合电极具有电阻并联效果,CNT阴极导电性能提高.场致发射特性测试表明ITO/Ti基CNT阴极的场致发射电流达到384μA/cm2,较普通ITO基CNT阴极的场致发射电流有显著提高,能够激发测试阳极发出均匀、稳定的高亮度荧光.制作ITO/Ti复合电极是实现场致发射稳定、均匀的低功耗CNT阴极的有效途径. 相似文献
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We have calculated the ground-state energy of the symmetric quantum-dot pattern by the ab initio calculation method, i.e. unrestricted Hartree-Fock-Roothaan (UHFR) method based on the Gaussian basis, and studied their electric capacitance spectra, assuming each quantum dot of quantum-dot pattern to be confined in a three-dimensional spherical potential well of finite depth. For the systems in question, our results show that our method and theoretical model not only give the electric capacitance peaks similar to s-shell and p-shell atom-like quantum dot, but also show some new fine-structure of electric capacitance in the symmetric quantum-dot pattern system. This method might be a feasible tool to study few-electron problems on the symmetric quantum-dot pattern system. 相似文献
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The difference in temporal structures of retinal ganglion cell spike trains between spontaneous activity and firing activity after contrast adaptation is investigated. The Lempel-Ziv complexity analysis reveals that the complexity of the neural spike train decreases after contrast adaptation. This implies that the behaviour of the neuron becomes ordered, which may carry relevant information about the external stimulus. Thus, during the neuron activity after contrast adaptation, external information could be encoded in forms of some certain patterns in the temporal structure of spike train that is significantly different, compared to that of the spike train during spontaneous activity, although the firing rates in spontaneous activity and firing activity after contrast adaptation are sometime similar. 相似文献
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Experimental Study on Electrostatic with Two Guiding of Supersonic D20 Molecular Beam Charged Wires
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We demonstrate the guiding of a supersonic heavy-water (D2O) molecular beam using a hollow electrostatic field generated by the combination of two parallel charged-wires and two grounded metal-plates, and report some new and preliminary experimental results. In the experiment, we detect the guiding signals by using the method of time-of-flight mass spectrum and study the dependence of the relative transmission of the beam guide on the guiding voltage. Our study shows that the relative transmission of the beam guide is increased linearly with increasing guiding voltage Vguid, and the number of the guided D20 molecules is at least increased by 89.4% when the guiding voltage is +20.0k V. Finally, some potential applications of our guiding scheme in the molecule optics are briefly discussed. 相似文献
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