Shape-induced phase transition of vortex domain structures in ferroelectric nanodots and their controllability by electrical and mechanical loads

(整期优先)网络出版时间:2017-02-12
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Shape-inducedphasetransitionofvortexdomainstructures(VDSs)inBaTiO_3(BT)nanodotsunderopencircuitboundaryconditionhavebeeninvestigatedusinganeffectiveHamiltonianmethod.OurcalculationindicatesthetetragonalVDSmissingincubicBTnanodotscanbeinducedbyvaryingtheshapeofananodotfromcubetoplatelet.Interestingly,anovelVDSisfoundinBTnanoplateletsinoursimulations.Furtherinvestigationshowsthatitisaresultofcompromisebetweenthegroundstateandthesymmetryoftheshapeofthenanodot.Furthermore,basedonthenovelVDS,routesofcontrollingVDSsgovernedbyhomogeneouselectricfieldanduniformstressarediscussed.Inparticular,ourresultsshowthepossibilityofdesigningmulti-statesdevicesbasedonasingleVDS.