Interfacial Charge Engineering in Ferroelectric-Controlled Mott Transistors
Ferroelectric field effect controlled Mott transistors (FerroFET) have been widely studied for developing nonvolatile memory and logic applications. One of key challenges is to achieve substantial modulation of the carrier density of channel. To date, only moderate resistance switching has been reported at room temperature. In this work, we employ the transfer effects in two strongly correlated oxides, Sm0.5Nd0.5NiO3 (SNNO) and La0.67Sr0.33MnO3 (LSMO), to realize a giant enhancement in the performance of the FerroFETs. The charge transfer between SNNO/LSMO can lead a density modulation in SNNO that is comparable with the polarization field of PZT, as revealed by XPS and XAS measurements and confirmed by first principles density functional theory calculations. We find for the same channel thickness, the room temperature resistance switching ratio is up to two orders of magnitude higher in the SNNO/LSMO channel, which is attributed to the overlap between the charge screening region at the PZT/SNNO interface and the charge transfer region at the SNNO/LSMO interface. Our study points to an effective strategy to realize high performance FerroFET via interfacial charge design.