Coupling of switchable ferroelectric polarization with the carrier transport in an adjacent semiconductor enables a robust, non-volatile manipulation of the conductance in a host of low-dimensional systems, including the two-dimensional electron liquid that forms at the LaAlO3-SrTiO3 interface. However, the strength of the gate-channel coupling is relatively weak, limited in part by the electrostatic potential difference across a ferroelectric gate. Compositionally grading of PbZr1-xTixO3 ferroelectric gates enables a more than twenty-fivefold increase in the LAO/STO channel conductance on/off ratios. Incorporation of polarization gradients in ferroelectric gates can enable significantly enhanced performance of ferroelectric non-volatile memories.