Reversible insulator-metal transition of LaAlO3/SrTiO3 interface for nonvolatile memory
نویسندگان
چکیده
We report a new type of memory device based on insulating LaAlO₃/SrTiO₃ (LAO/STO) hetero-interface. The microstructures of the LAO/STO interface are characterized by Cs-corrected scanning transmission electron microscopy, which reveals the element intermixing at the interface. The inhomogeneous element distribution may result in carrier localization, which is responsible for the insulating state. The insulating state of such interface can be converted to metallic state by light illumination and the metallic state maintains after light off due to giant persistent photoconductivity (PPC) effect. The on/off ratio between the PPC and the initial dark conductance is as large as 10⁵. The metallic state also can be converted back to insulating state by applying gate voltage. Reversible and reproducible resistive switching makes LAO/STO interface promising as a nonvolatile memory. Our results deepen the understanding of PPC phenomenon in LAO/STO, and pave the way for the development of all-oxide electronics integrating information storage devices.
منابع مشابه
Interface Fermi States of LaAlO 3 / SrTiO 3 and Related Heterostructures CANCELLIERI , Claudia
The interfaces of LaAlO3/SrTiO3 and (LaAlO3)x(SrTiO3)1−x/SrTiO3 heterostructures have been investigated by soft x-ray photoelectron spectroscopy for different layer thicknesses across the insulator-to-metal interface transition. The valence band and Fermi edge were probed using resonant photoemission across the Ti L2,3 absorption edge. The presence of a Fermi-edge signal originating from the pa...
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