Ferroelectric control of charge-to-spin conversion in WTe2

Ferroelectric materials hold great potential for alternative memories and\ncomputing, but several challenges need to be overcome before bringing the ideas\nto applications. In this context, the recently discovered link between electric\npolarization and spin textures in some classes of ferroelectrics expands the\nperspectives of the design of devices that could simultaneously benefit from\nferroelectric and spintronic properties. Here, we explore the concept of\nnon-volatile ferroelectric control of charge-to-spin conversion in semimetallic\nWTe$_2$, which may provide a way for non-destructive read-out of the polar\nstate. Based on the first-principles simulations, we show that the\nRashba-Edelstein effect (REE) that converts electric currents into spin\naccumulation switches its sign upon the reversal of the electric polarization.\nThe numerical values of REE, calculated for the first time for both bulk and\nbilayer WTe$_2$, demonstrate that the conversion is sizable, and may remain\nlarge even at room temperature. The ferroelectric control of spin transport in\nnon-magnetic materials provides functionalities similar to multiferroics and\nallows the design of memories or logic-in-memory devices that combine\nferroelectric writing of information at low power with the spin-orbit read-out\nof state.\n