Open AccessNon-equilibrium resistive states of superconducting NbN microstrips in a transverse magnetic field
Author(s) -
Sébastien Adam,
Luc Piraux,
Sébastien Michotte,
D. Lucot,
D. Mailly
Publication year - 2009
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/150/5/052002
Subject(s) - condensed matter physics , instability , resistive touchscreen , superconductivity , magnetic field , current (fluid) , materials science , discontinuity (linguistics) , voltage , biasing , mechanics , magnetic flux , physics , electrical engineering , engineering , quantum mechanics , mathematical analysis , mathematics , thermodynamics
Applying current in type-II superconducting sub-micron size structures often leads to a discontinuity of the current-voltage characteristic as the instability current is reached. Also voltage-bias mode allows to avoid such an abrupt switch to the normal state, and gives a relevant outlook of the involved resistive phenomenons. Current and voltage-bias measurements on NbN microbridges with a constriction are reported here as a function of temperature and transverse magnetic field. Starting from a 75 nm -thick sputtered film, 160 nm -wide microstrips were patterned with an half-wide section constriction in their middle. From the current-bias curves it appears that the discontinuities are due to a flux flow instability that rapidly evolves in a hot-spot. Moreover applying the voltage reveals several dissipative states that leads to successive S-shaped current oscillations in a small current range. Formation of vortex channels can be considered to explain these features.Anglai