Fig. 3: Ferroelectric switching and interfacial Dzyaloshinskii–Moriya interaction (DMI).
From: Magnetoelectric phase transition driven by interfacial-engineered Dzyaloshinskii-Moriya interaction
a Out-of-plane PFM images of the I3/T6 superlattice at 3.7 K, the relative dark and bright contrasts in-phase (left panel) and amplitude (right panel) indicate upward and downward ferroelectric domains. b Electron energy loss spectroscopy (EELS) of Ti L2,3 for the I3/T6 superlattice corresponding to the detailed electronic structure. The intensity ratios of eg to t2g of the Ti L2,3 edges are reduced at the perovskite interface (red curve) which is different from that at the Ruddlesden–Popper interface (black curve). The distinct electronic structures between two interfaces could induce an effective electric field (Eeff) in the STO. c Temperature-dependent resonant peak intensity of spin-wave for I3/T6 superlattice. When temperature increases, this resonant peak was dramatically suppressed as the decrease of magnetization (orange curve). Inset shows the temperature dependence of spin-wave spectra by BLS measurements. d BLS spectra for the I3/T6 superlattice. The difference of frequency (\({\triangle f}\) = 0.19 GHz) between anti-Stokes (black curve) and Stokes (red curve) peaks demonstrates that the interfacial DMI exists in this superlattice. The error bars in (c) and (d) are standard errors of measurements.
