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arXiv · 1111.5088

Thermal hopping and retrapping of a Brownian particle in the tilted periodic potential of a NbN/MgO/NbN Josephson junction

Luigi Longobardi·Davide Massarotti·Giacomo Rotoli·Daniela Stornaiuolo·Gianpaolo Papari·Akira Kawakami·Giovanni Piero Pepe·Antonio Barone·Francesco Tafuri
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Abstract

We report on the occurrence of multiple hopping and retrapping of a Brownian particle in a tilted washboard potential. The escape dynamic has been studied experimentally by measuring the switching current distributions as a function of temperature in a moderately damped NbN/MgO/NbN Josephson junction. At low temperatures the second moment of the distribution increases in agreement with calculations based on Kramers thermal activation regime. After a turn-over temperature T*, the shape of the distributions starts changing and width decreases with temperature. We analyze the data through fit of the switching probability and Monte Carlo simulations and we find a good agreement with a model based on a multiple retrapping process.

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Luigi Longobardi, Davide Massarotti, Giacomo Rotoli, Daniela Stornaiuolo, Gianpaolo Papari, Akira Kawakami, Giovanni Piero Pepe, Antonio Barone, Francesco Tafuri. 2011-11-22. Thermal hopping and retrapping of a Brownian particle in the tilted periodic potential of a NbN/MgO/NbN Josephson junction. https://doi.org/10.1103/physrevb.84.184504

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