1. A non-volatile memory device, comprising: a re-writeable non-volatile two-terminal memory element having a first terminal and a second terminal and configured to retain stored data in the absence of electrical power, the memory element including a conductive oxide layer including mobile ions, an electronically insulating layer in contact with the conductive oxide layer and having a first thickness and a first dielectric constant, the electronically insulating layer is permeable to the mobile ions, and an ion barrier layer in contact with the electronically insulating layer and having a second thickness and a second dielectric constant, the ion barrier layer is not permeable to the mobile ions and is operative to prevent mobile ion transport through an interface where the ion barrier layer and the electronically insulating layer contact each other, wherein a combined thickness of the ion barrier layer and the electronically insulating layer is approximately 50 Å or less, and wherein the conductive oxide layer, the electronically insulating layer, and the ion barrier layer are electrically in series with one another and with the first and second terminals.