| Authors | سمیرا سامانی فر-محمد الماسی کاشی-عبد العلی رمضانی-مصطفی علیخانی |
|---|---|
| Journal | J MAGN MAGN MATER |
| Paper Type | Full Paper |
| Published At | 2015-1-01 |
| Journal Grade | ISI |
| Journal Type | Typographic |
| Journal Country | Iran, Islamic Republic Of |
| Journal Index | ISI ,SCOPUS |
Abstract
FeCoNi nanowire arrays(175nm in diameter and lengths ranging from 5 to 40 μm) were fabricated into nanopores o fhard-anodized aluminum oxide templates using pulsed ac electrodeposition technique. Increasing thelengthhadnoconsiderableeffectonthecompositionandcrystallinecharacteristicsof Fe47Co38Ni15 nanowires(NWs).Byeliminatingthedendritesformedatthebottomofthepores,we report acarefulinvestigationontheeffectofmagnetostaticinteractionsonmagneticpropertiesandthe effect ofnanowirelengthonreversalmodes.Hysteresisloopmeasurementsindicatedthatincreasingthe length decreasescoercivityandsquarenessvalues.Ontheotherhand, first-order reversalcurvemea- surements showalinearcorrelationbetweenthemagnetostaticinteractionsandlengthofNWs.Com- paring reversalmodesoftheNWsbothexperimentallyandtheoreticallyusingangulardependenceof coercivity,we find thatwhen Lr22 μm, avortexdomainwallmodeisonlyoccurred.When L422 μm, a non-monotonicbehaviorindicatesatransitionfromthevortextotransversedomainwallpropagation. As aresult,acriticallengthwasfoundabovewhichthetransitionbetweenthereversalmodesisoc- curred duetheenhancedinteractions.Thetransitionanglealsoshiftstowardalowerangleasthelength increases. Moreover,withincreasinglengthfrom22to31 μm, thesingledomainstructureofNWs changes toapseudosingledomainstate.Amultidomain-likebehaviorisalsofoundforthelongestNWs length.