Evidence for Supercurrent Quantization in Interfacial Josephson Junctions
نویسندگان
چکیده
We observe a series of discontinuities in the above gap current-voltage characteristics of highly transmissive NbySi superconductor-semiconductor interfaces. The bias at which each switch occurs decreases in quantized steps as a function of temperature and magnetic field. The observed step size is the same for both dependencies. We propose that the steps correspond to supercurrent quantization through granular Josephson junctions formed near the interface. [S0031-9007(97)05103-X]
منابع مشابه
Observation of spin-triplet superconductivity in Co-based Josephson junctions.
We have measured a long-range supercurrent in Josephson junctions containing Co (a strong ferromagnetic material) when we insert thin layers of either PdNi or CuNi weakly ferromagnetic alloys between the Co and the two superconducting Nb electrodes. The critical current in such junctions hardly decays for Co thicknesses in the range of 12-28 nm, whereas it decays very steeply in similar junctio...
متن کاملMagnetically-driven colossal supercurrent enhancement in InAs nanowire Josephson junctions
The Josephson effect is a fundamental quantum phenomenon where a dissipationless supercurrent is introduced in a weak link between two superconducting electrodes by Andreev reflections. The physical details and topology of the junction drastically modify the properties of the supercurrent and a strong enhancement of the critical supercurrent is expected to occur when the topology of the junctio...
متن کاملJosephson current in ballistic superconductor-graphene systems
We calculate the phase, the temperature and the junction length dependence of the supercurrent for ballistic graphene Josephson junctions. For low temperatures we find nonsinusoidal dependence of the supercurrent on the superconductor phase difference for both short and long junctions. The skewness, which characterizes the deviaton of the current-phase relation from a simple sinusoidal one, sho...
متن کاملDissipative enhancement of the supercurrent in Tl2Ba2CaCu2O8 intrinsic Josephson junctions.
We have measured dissipation-induced localization of the reaction coordinate for a metastable-state decay process in a model system with moderate damping. Specifically, the supercurrent in an array of Tl2Ba2CaCu2O8 intrinsic Josephson junctions is larger when all the junctions are in the zero-voltage state than when one or more junctions are in the voltage state since the dissipation is larger ...
متن کاملEffect of Impurities on the Josephson Current through Helical Metals: Exploiting a Neutrino Paradigm.
In this Letter we study the effect of time-reversal symmetric impurities on the Josephson supercurrent through two-dimensional helical metals such as on a topological insulator surface state. We show that, contrary to the usual superconducting-normal metal-superconducting junctions, the suppression of the supercurrent in the superconducting-helical metal-superconducting junction is mainly due t...
متن کامل