Parallel to anti-parallel switching of magnetic moments in LSMO twisted bilayer membranes on PMN-xPT

Strain-mediated magnetoelectric (ME) coupling in ferroelectric (FE) and ferromagnetic (FM) heterostructures provides an exciting path towards the development of next-generation memory storage and sensing technologies [1-2], particularly for low-power applications [3-4]. Theory predicts that strain can control magnetic orientation/rotation in heterostructures with noncollinear easy axes [5]. When stacking free-standing membrane thin films of La(1-x)Sr(x)MnO₃ (LSMO) onto giant piezoelectric (1-x)Pb(Mg_1/3Nb_2/3)O₃-(x)PbTiO₃ (PMN-xPT) substrates, we can vary the twist-angle between individual LSMO layers. By utilizing this twist angle degree of freedom, we attempt to achieve parallel to antiparallel magnetic switching of magnetic moments in the LSMO/PMN-PT heterostructures. We will discuss experiments involving in-operando Polarized Neutron Reflectometry (PNR) which can measure the depth dependence of magnetism. Subsequent fitting/analysis using REFL1D software helps to determine how individual layers of LSMO respond to the strain provided by PMN-xPT, as well as reveal any interactions that may arise between the LSMO membranes.

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