CC-07: A Robust High-temperature Multiferroic Device with Tunable Magnetic Chiral Fluctuation

We integrated Pt/La0.5Ba0.5MnO3 ultrathin films with the PbZr0.2Ti0.8O3 ferroelectric and obtained several unprecedented results. Apart from strong Topological Hall Effect (THE) measurable across a wide temperature range, we also demonstrate reversible ON/OFF tuning of THE signal by ferroelectric polarization switching, indicating creation and annihilation of magnetic Skyrmions by short voltage pulses. Regarding the exact mechanism of magnetoelectric coupling, although the concept of selective electrostatic doping between eg orbitals of manganite cations has been well-known, our magnetoelectric polarity is found opposite to the earlier observations, which is best explained by a novel phase transition between C-type antiferromagnetic and ferromagnetic. The crucial innovation here originates from our opposite choice of layer stacking sequence which reverses the sign of tetragonal strain of the manganite unit cell, therefore providing a complementary insight where strain and polarization switching act in tandem. The relationship between the phase transition and tuning of THE is supported by micromagnetic simulations.References: 1. Nature 408, pages 944 (2000) 2. Physical Review Letters, 104, 127202 (2010) 3. Science 336, 198 (2012) 4. Nature Communications 7, 12669 (2016) 5. Nature Materials 17, 1087 (2018) 6. Nature Materials 18, 1054 (2019) 7. Physical Review Letters 124, 107201 (2020)