Back to Search Start Over

Study of phase dynamics in moderately damped Josephson junctions

Authors :
Daniela Stornaiuolo
Davide Massarotti
Akira Kawakami
Luigi Longobardi
Giovanni Piero Pepe
Luca Galletti
G. Rotoli
Francesco Tafuri
D., Massarotti
L., Longobardi
D., Stornaiuolo
L., Galletti
Rotoli, Giacomo
A., Kawakami
G. P., Pepe
Tafuri, Francesco
Massarotti, D.
Longobardi, L.
Stornaiuolo, Daniela
Galletti, L.
Rotoli, G.
Kawakami, A.
Pepe, GIOVANNI PIERO
Publication Year :
2013

Abstract

The moderately damped regime (MDR) in a Josephson junction (JJ) is quite distinct from the well-known case of underdamped systems and quite common in devices characterized by low critical currents. Measurements of switching current distribution (SCD) are a direct way of discriminating the phase dynamics and the transport also in nontrivial cases of moderate damping. MDR is going to be more and more common with advances in nanopatterning superconductors and in materials science finalized to build hybrid devices. We report on measurements of SCDs, both in the thermal and quantum regime, on moderately damped NbN/MgO/NbN JJs. A transition from the Thermal Activation (TA) regime to Macroscopic Quantum Tunnelling (MQT) occurs at about 90 mK, while above 1.6 K a phase diffusive dynamics is clearly observed. The combined analysis of these regimes through numerical simulations allowed us to extract the fundamental parameters, which completely characterize the phase dynamics of such moderately damped JJs.

Details

Database :
OpenAIRE
Accession number :
edsair.doi.dedup.....ce45c088f5ecee32289fb05813d1567e