6533b858fe1ef96bd12b65bd
RESEARCH PRODUCT
Metal frame as local protection of superconducting films from thermomagnetic avalanches
Tom H. JohansenYuri GalperinPavlo MikheenkoIlari MaasiltaJ. I. VestgårdenS. Chaudhurisubject
Materials sciencemetal framesthermomagnetic avalanchesFOS: Physical sciencesGeneral Physics and AstronomyFluxchemistry.chemical_element02 engineering and technology01 natural sciencesSuperconductivity (cond-mat.supr-con)AluminiumCondensed Matter::Superconductivity0103 physical sciences010306 general physicsSuperconductivitysuperconducting filmsResistive touchscreenta114Condensed matter physicsCondensed Matter - SuperconductivityConductanceThermomagnetic convection021001 nanoscience & nanotechnologyAvalanche breakdownlcsh:QC1-999Creepchemistry0210 nano-technologylcsh:Physicsdescription
Thermomagnetic avalanches in superconducting films propagating extremely fast while forming unpredictable patterns, represent a serious threat for the performance of devices based on such materials. It is shown here that a normal-metal frame surrounding a selected region inside the film area can provide efficient protection from the avalanches during their propagation stage. Protective behavior is confirmed by magneto-optical imaging experiments on NbN films equipped with Cu and Al frames, and also by performing numerical simulations. Experimentally, it is found that while conventional flux creep is not affected by the frames, the dendritic avalanches are partially or fully screened by them. The level of screening depends on the ratio of the sheet conductance of the metal and the superconductor in the resistive state, and for ratios much larger than unity the screening is very efficient.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-01-04 | AIP Advances |