共查询到20条相似文献,搜索用时 31 毫秒
1.
在SrTiO3(STO)基片上制作了Tl-2212双晶约瑟夫森结,并对其进行了微波辐照下的I-V特性测试,观察到了夏皮罗台阶,符合约瑟夫森电压-频率关系.利用数值仿真对约瑟夫森结建立了RCSJ模型,仿真结果与实验数据符合较好,利用此模型深入研究了噪声对结动态特性的影响,解释了噪声影响下结的微波感应台阶幅度减小和极小值展宽现象,提出了有效噪声温度为工作温度和外部噪声的等效温度之和.
关键词:
RCSJ模型
噪声
Tl-2212双晶约瑟夫森结 相似文献
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Cooper-pair number-phase quantization analysis in double-Josephson-junction mesoscopic circuit coupled by a capacitor
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This paper examines the quantization of mesoscopic circuit including Josephson junctions. Following Feynman's assumption, via the Hamilton dynamic approach and by virtue of the entangled state representation, it constructs Hamiltonian operator for the double-Josephson-junction mesoscopic circuit coupled by a capacitor. Then it uses the Heisenberg equation of motion to derive the induction voltage across each Josephson junction. The result manifestly shows how the voltage is affected by the capacitance coupling. 相似文献
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通过超低温实验直接测量了制备的全铌Josephson结的电压源驱动RCSJ模型的I-V特性曲线。建立了Josephson结在电路仿真软件EWB中的模型,极大的方便了Josephson结及相关电路的仿真研究。利用这一新模型对Josephson结的基本特性进行了较为系统的研究,包括RSJ模型和RCSJ模型的直流驱动I-V特性曲线。 相似文献
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We have experimentally studied a small Josephson junction array in the presence of microwave irradiation. The array has comparable energy scales for single-charge effects and the Josephson effect, resulting in a discrete set of macroscopic eigenenergy levels. Excitation of the array by low-power microwaves is possible at frequencies where the photon energy matches the level spacing. The microwave frequency and amplitude dependence show that the excitation mechanism involves resonant quantum coherent dynamics of the array. 相似文献
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采用嵌入Fabry-Perot谐振腔的方式,研究了Tl2Ba2CaCu2O8(Tl-2212)高温超导薄膜双晶约瑟夫森结的毫米波辐照特性.重点研究了双晶约瑟夫森结与Fabry-Perot谐振腔的耦合特性,发现放置在谐振腔中的结的位置、角度、结的图形以及Fabry-Perot谐振腔中两镜面间的距离等对耦合都有很大的影响.通过精细调节这些参数,可使双晶约瑟夫森结与外加毫米波达到最佳耦合.在最佳耦合情况下,能观察到9级明显的夏皮罗台阶.利用Fabry-Perot谐振腔技术,解决了约瑟夫森结与毫米波的耦合问题,为高温超导约瑟夫森结的毫米波及太赫兹波的辐射和检测研究奠定了基础. 相似文献
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R. De Luca 《Physics letters. A》2011,375(24):2441-2443
The current-phase relations of a double-barrier Josephson junction with a thin intermediate electrode show deviations from the usual sinusoidal dependence of a single Josephson junction. The skewness of these curves can be analytically found for small values of the coupling between the two outer electrodes of the double-barrier Josephson junction. 相似文献
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We consider a two-level system (TLS) with energy level separation plankvOmega0 inside a Josephson junction. The junction is shunted by a resistor R and is voltage V biased. If the TLS modulates the Josephson energy and/or is optically active, it is Rabi driven by the Josephson oscillations in the running phase regime near the resonance 2eV=plankvOmega0. The Rabi oscillations, in turn, translate into oscillations of current and voltage that can be detected in noise measurements. This effect provides an option to fully characterize the TLS inside Josephson junction and to find the TLS's contribution to the decoherence when the junction is used as a qubit. 相似文献
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《Physics letters. A》1988,132(1):20-24
A planar Josephson junction is used as a detector for the radiation emitted by a long Josephson junction oscillator dc-biased on a zero-field singularity. We observe Josephson current suppression and 300 μV radiation induced singularities in the current-voltage characteristic of the detector junction. 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
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A. S. Malishevskii V. P. Silin S. A. Uryupin S. G. Uspenskii 《Physics of the Solid State》2005,47(10):1805-1813
A motion of slow and fast vortices in a waveguide-coupled Josephson junction induced by a transport current flowing through the entire structure is studied; the coupling is not assumed to be weak. For a fast vortex, conditions are established under which current oscillations due to energy dissipation via Cherenkov radiation of Swihart waves become comparable to the current compensating for ohmic losses in the Josephson junction, waveguide, and adjacent superconductors. For a slow vortex, it is proved that intermediate and strong couplings of the Josephson junction to the waveguide shift current oscillations to the velocity range below the Swihart velocity of the Josephson junction. 相似文献
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JETP Letters - The dynamics of a nanomagnet coupled to a Josephson junction has been studied. Although a magnetic field induced by the superconducting current in the Josephson junction is very... 相似文献
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《Physics letters. A》1987,123(4):191-196
The problem of ultrasonic wave propagation in narrow Josephson junctions at nonzero temperature has been investigated. Using the derived solution of the nonstationary Fokker-Planck equation, the total current flowing through the narrow Josephson junction is calculated, and the coefficient of the ultrasonic wave passage through the Josephson junction is determined. The singularity of this coefficient is studied in the ultrasound amplification mode associated with the transformation of coherent binding energy of the contact into ultrasonic waves, and the possibility of experimental measurement of the lifetime of the Josephson junction in the metastable state under the conditions of maximum ultrasound amplification by the contact is discussed. 相似文献
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Coherent and correlated states of a Josephson junction are constructed. Quantum current and voltage noises are calculated. The influence of an external current and of parametric buildup on the Josephson junction is discussed. The feasibility in principle of exciting correlated and coherent states in a Josephson junction is suggested.High-Energy Electron Laboratory. Translated from Preprint No. 89 of the Lebedev Physics Institute, Academy of Sciences of the USSR, Moscow, 1989. 相似文献
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The response of an intergranular Josephson junction to displacements of an Abrikosov vortex in a superconducting polycrystal is studied theoretically. The vortex filament in the vicinity of the junction excites a tunnel current in the junction and also generates a Josephson vortex with which it merges upon emergence at the surface of the junction. It is shown that the process of the Josephson vortex formation passes through a stage of overcoming a potential barrier, whose height depends on the distance between the Abrikosov vortex and the junction, as well as on the effective thickness of the junction, which is determined by the characteristic grain size, grain anisotropy, and the intensity of the intergranular coupling. The magnetic field dependence of the critical current of the intergranular Josephson junction is determined for various grain and intergranular parameters, as well as for the triangular and square configurations of the Abrikosov vortex lattice. The results indicate that a high degree of texturing in the grain size, anisotropy, and intensity of intergranular coupling is very important for obtaining high critical currents in pure polycrystalline materials. 相似文献
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在He等人所做的嵌入到Fabry-Perot谐振腔中约瑟夫森结阵列的微波辐照研究基础上,提出了同时实现约瑟夫森结阵列阻抗匹配和相位锁定的方法,进行了相关的电磁仿真和数值计算.双晶约瑟夫森结阵列被制作在YSZ双晶基片上,同时被嵌入到Fabry-Perot谐振腔内.通过在基片上制作与结阵列集成的串联馈电半波偶极天线阵,并对其结构进行优化实现了结与天线的匹配,数值计算表明结的辐射效率达到94%;利用天线阵辐射场的特征和对模型合理的设计,使Fabry-Perot谐振腔和基片同时谐振在合适的模式下,从而使结阵列与谐
关键词:
约瑟夫森结阵列
阻抗匹配
相位锁定
Fabry-Perot谐振腔 相似文献
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Hideaki Takayanagi R. Inoue T. Akazaki K. Tanaka I. Suemune 《Physica C: Superconductivity and its Applications》2010,470(19):814-817
Superconducting transport is measured between two superconducting electrodes at the n-type semiconductor side of a superconductor-based LED where a Josephson junction is formed. The characteristics of the Josephson junction are found to be modulated by applying voltage to the normal electrode at the p-type semiconductor side. The Josephson junction characteristics show an extraordinary sensitivity to the radiative recombination process, which we estimate as the recombination efficiency. 相似文献