共查询到18条相似文献,搜索用时 156 毫秒
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为方便约瑟夫森结及其相关电路的仿真研究,根据约瑟夫森方程首次提出了约瑟夫森结的电路模型,给出了具体的电路原理图,并进行了封装.利用这个模型可以对约瑟夫森结的相关特性进行深入系统的仿真研究,这样不必自己编写程序对系统的微分方程进行数值求解,大大提高了工作效率.利用这个模型,对约瑟夫森结的混沌行为、相位锁定特性、RSFQ电路和SQUID进行了研究,结果说明了模型的正确性和实用性,模型的建立对于促进超导器件的相关研究具有一定意义. 相似文献
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提出了超导约瑟夫森结模型(并联电阻—电容结模型),给出了约瑟夫森效应的一些重要结果。在分析约瑟夫森结电路方程时,研究了其中出现的混沌特性和子台阶现象。计算获得的结果对混沌数字通信和超导电子学的应用将起到重要作用。 相似文献
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为实现高性能处理器,超导RSFQ(快速单磁通量子)电路被提出.该电路主要由超导约瑟夫森结和超导无源传输线组成,对其建模分析是超导RSFQ电路设计的基础.本文提出了基于FDTD(时域有限差分)的约瑟夫森结与超导传输线的协同分析方法.该方法采用FDTD数值方法求解超导传输线的电报方程.在超导传输线与约瑟夫森结交界处的非线性边界条件上,采用了Newton-Raphson迭代算法.数值结果表明,本文提出的约瑟夫森结和超导传输线的协同分析方法与WRspice仿真软件相比具有相同精度,且运算效率显著提高. 相似文献
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系统地研究了超导亚毫米波阵列振荡器的相位锁定问题。为使超导振荡器达到高工作频率、窄线宽和高稳定的性能,约瑟夫森结与结之间的相位必须相互锁定。相位锁定可以通过结与结之间的耦合电路得以实现。通过对振荡器的各种耦合电路的比较表明,蝴蝶领结天线结构是一个比较适合约瑟夫森振荡器相位锁定的耦合电路。本文提出了一种超导亚毫米波阵列振荡器模型并对其进行了模拟计算与分析,仿真得出了振荡器各项参数值,并给出了相位锁定的条件。 相似文献
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本文系统地研究了超导亚毫米波阵列振荡器。首先介绍了约瑟夫森结阵列振荡器的基本原理 ,然后根据原理引出超导亚毫米波阵列振荡器的模型 ,最后 ,根据约瑟夫森原理 ,对超导亚毫米波阵列振荡器的模型进行了模拟和分析 ,仿真得出了振荡器各项参数值 ,并给出了相位锁定的条件 相似文献
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新的电子器件不断涌现,当需要新器件的模型进行仿真或制作印制电路板时,原有的Multisim元器件库就不能满足用户的需求,需建立与编辑新元器件.介绍利用Maxim公司高亮LED驱动器MAX16823的Spice模型在Multisim 8中建立MAX16823新元器件的方法;并以555定时器及MAX16823驱动器组成的脉宽调制高亮度LED驱动电路为例,通过设置高亮LED参数,以及调节电阻RP即改变555定时器输出方渡信号的占空比等对电路进行仿真分析,验证了所建立的MAX16823新元器件的功能是正确的.结果表明利用该方法可以快速、高效地在Multisim中建立新元器件. 相似文献
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约瑟夫森混合器是一种能够生成纠缠量子微波信号的电路。建立了约瑟夫森混合器的等效电路模型,对三波混频哈密顿量进行量子化,研究了约瑟夫森结的临界电流、分路线性电感、谐振器传输线等效电感以及外加穿过环路磁通对三波混频强度的影响。仿真结果表明,约瑟夫森结的临界电流决定了选择的线性电感最大值,而对三波混频强度影响不大;线性电感的大小决定了外加穿过环路磁通的最优值以及三波混频强度的最大值;谐振器传输线等效电感在允许范围内越小越好。研究对于有效选择电路元器件参数,提高纠缠量子微波生成能力有重要价值。 相似文献
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Chen J. Yamashita T. Sasahara H. Suzuki H. Kurosawa H. Hirotsu Y. 《Applied Superconductivity, IEEE Transactions on》1991,1(2):102-107
The DC and AC Josephson effects were observed in YBa2Cu 3O7-a (YBCO) bridges with metal-organic chemical vapor deposited (MOCVD) thin films on (100)MgO substrates. In TEM observations and X-ray analysis, the angle grain boundaries (AGBs) in these films were observed. Josephson junction resulting from the AGBs showed the semiconducting barrier junction property dominantly, and the AGBs consisted of YBCO with oxygen deficiency. Based on these results, the authors propose a three-terminal device with the Josephson junction. The Josephson junction can be prepared by depositing an epitaxial YBCO thin film with one AGB on a bicrystal (100)SrTiO3 or (100)Si substrate, and the insulated gate for the application of electric field to the AGB is formed over the junction. The supercurrent in the Josephson junction is controlled by the electric field effect of the semiconducting AGB in the junction 相似文献
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《Electron Devices, IEEE Transactions on》1980,27(10):1934-1944
In this paper, we deal with a model of a specific Josephson microwave circuit, that of a Josephson oscillator, and show that the RF behavior of a real Josephson oscillator may be predicted from a knowledge of the experimentally measured microwave circuit parameters, the junction critical current, and junction shunt resistance. Based on observations made with an electronic analog, we present an approximate analytical method for calculating the junction impedance or, rigorously speaking, the appropriate single sinusoidal-input describing function. Emphasis is placed on the proper use of the impedance, for example, in calculating the operating point and the expected output power of the oscillator. The circuit model used is that of a junction, described by the resistively shunted junction model, coupled to a seriesLCR resonance. Further confirmation of the validity of the circuit-theory approach is obtained by using the injection-locked oscillator theory of Kurokawa to predict the in-lock amplitude variation of a Josephson oscillator exposed to a weak synchronizing signal. Experimental data describing the amplitude variation and output power of an oscillator consisting of a point-contact junction placed in a 9.72-GHz coaxial resonator are presented. The data demonstrate the reasonable agreement obtained when the measured critical current and shunt resistance are used with the analytical expression for the junction impedance and the circuit theory to predict the RF behavior of a Josephson oscillator. Circuits more complex than our specific example may be handled by means of describing function techniques recently developed in the area of nonlinear solid-state microwave devices. 相似文献
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We have measured the microwave characteristics of Josephson junction at liquid nitrogen temperature by using microwave network analyser. Based upon these experimental results we present a microwave circuit model of Josephson junction at liquid nitrogen temperature and calculate the parameters of microwave circuit model of Josephson junction.
相似文献14.
The switching dynamics of a double-barrier Josephson junction is analyzed as a function of the microscopic properties of its electrodes. In particular, it is found that the nonstationary behavior of the Josephson phase difference is very sensitive to dissipation mechanisms acting inside the intrinsic shunt. The leading factor that determines the dissipation is the local electron density of states N(E) inside the electrodes. The roles of junction geometry, electrode purity, and interface quality are discussed and how they affect the details of N(E), hence the resulting phase dynamics. The microscopic analyses allow optimization of the performance of double-barrier Josephson junction-based rapid-single-flux-quantum circuits in two ways: 1) decreasing the switching time of Josephson elements and 2) reducing the excess wiring. Such an analysis is facilitated with the aid of a lumped circuit representation which generalizes the nonlinear resistive-shunted-junction model. 相似文献
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《Electron Device Letters, IEEE》1982,3(2):29-31
A data processing circuit implemented in 2.5 µm Josephson Current Injection Logic (CIL) has been designed and successfully tested at subnanosecond cycle times, corresponding to a data processing rate of over 1 Gigabit per second. The circuit was implemented using a total of 177 devices (102 logic gates), and is the most complex Josephson logic circuit operated so far. The minimum cycle time achieved was 665 ps (5 logic stages), the corresponding chip power dissipation being about 350 µW. The performance was ultimately limited by variations in junction critical currents and resistor values that were larger than the design values. 相似文献
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Muhammad Taher Abuelma'atti 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(6):1299-1310
In this paper a simple mathematical model is presented for the inherent resistive nonlinearity of a Josephson junction. By incorporating this model in the RSJ model of the Josephson junction, series expressions are obtained for the harmonic and intermodulation performance of Josephson junctions irradiated by multisinusoidal signals. Special cases are considered where the series expressions can be reduced to simple analytical expressions. 相似文献
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《Applied Superconductivity》1997,5(7-12):393-398
Current–voltage characteristics of vertically stacked all-NbCN Josephson junctions has been investigated with a purpose to use them as an element of integrated circuits. It has been shown that increases of microwave power in the junction definition process using electron cyclotron resonance (ECR) etching causes reduction of the junction quality parameter. From results of a measurement of current–voltage characteristics for an array composed of five-fold vertically stacked NbCN/MgO/NbCN junctions, it has been found that a very high uniformity in critical currents can be achieved. 相似文献
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Tarutani Y. Hirano M. Kawabe U. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1989,77(8):1164-1176
Metallurgical and electrical properties of Nb and NbN films for use as Josephson junction electrodes and wiring layers are investigated. The crystallographic and superconducting properties necessary for Nb-based integrated circuit processes are clarified. Tunnel barrier structures of NbN-Nb oxide-NbN (Pb alloy) and Nb-Al oxide-Nb Josephson junctions have been analyzed and correlated with junction characteristics and critical current uniformity. It was found that the surface structure of a base electrode should be smooth to ensure that Josephson junctions have low leakage current and uniform critical current distribution. New types of Josephson junctions with artificial tunnel barriers such as amorphous Si or Mg oxide are reviewed. A variety of Josephson junction structures or processes have been developed for Nb-based Josephson integrated circuits in order to improve circuit performance. These include junction miniaturization, planarization, and stacked junction structures. These structures are mainly intended for Nb-Al oxide-Nb Josephson circuits. The Nb-Al oxide-Nb Josephson junction technology is by far the most advanced and has been used in logic and memory circuits, for example a 4-bit×4-bit parallel multiplier, a Josephson logic gate array, a 16-bit arithmetic logic unit, a 4-bit microprocessor, and 1-kb and 4-kb memory circuits 相似文献