Strain-mediated magnetoelectric coupling of 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 in heterostructures with noncollinear easy axes [5]. By stacking free-standing membrane thin films, which are released from their original substrates through various methods [6-8], we can vary the twist-angle between individual membrane layers which has paved the way for a new category of devices termed “twistronics.” [9] We want to utilize this twist angle degree of freedom to achieve parallel to antiparallel magnetic switching in twisted bilayers of La_(1-x)Sr_(x)MnO₃ (LSMO) transferred onto a giant piezoelectric (1-x)Pb(Mg_1/3Nb_2/3)O₃-(x)PbTiO₃ (PMN-xPT). We will discuss experiments involving in-operando Polarized Neutron Reflectometry (PNR) to measure the depth dependence of magnetism which helps us study how individual layers of LSMO respond to the strain provided by PMN-xPT.

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